1

US Investor Presentation

March 2010

O I L S E A R C H L I M I T E D

2

DISCLAIMER

While every effort is made to provide accurate and complete information, Oil Search Limited does not warrant that the information in this presentation is free from errors or omissions or is suitable for its intended use. Subject to any terms implied by law which cannot be excluded, Oil Search Limited accepts no responsibility for any loss, damage, cost or expense (whether direct or indirect) incurred by you as a result of any error, omission or misrepresentation in information in this presentation. All information in this presentation is subject to change without notice.

This presentation also contains forward-looking statements which are subject to particular risks associated with the oil and gas industry. Oil Search Limited believes there are reasonable grounds for the expectations on which the statements are based. However actual outcomes could differ materially due to a range of factors including oil and gas prices, demand for oil, currency fluctuations, drilling results, field performance, the timing of well work-overs and field development, reserves depletion, progress on gas commercialisation and fiscal and other government issues and approvals.

3

Oil Search Profile

Established in Papua New Guinea (PNG) in 1929

Operates all of PNG’s producing oil and gas fields. Current gross production ~40,000 boepd, net share ~21,000 boepd

PNG Government is largest shareholder with 15%. In early 2009, Govt issued exchangeable bond over shares to IPIC of Abu Dhabi

29% interest in PNG LNG Project, world scale LNG project operated by ExxonMobil. Project in construction, first LNG sales expected 2014

Significant further gas resources still to be commercialised plus exploration interests in PNG and Middle East/North Africa

Market capitalisation ~US$7 billion. Listed on ASX (Share Code OSH) and POMSOX, plus ADR programme (Share Code OISHY)

4

Oil Search Locations

Tunisia Iraq

Yemen

Papua New Guinea

Australia Brisbane

Sydney

Port Moresby(Head Office)

Kutubu Ridge Camp

Dubai

Sana’a

Tunis

5

2009 Performance Summary

Highlight of 2009 was PNG LNG Project development decision:

Less than two years from FEED to Sanction

Transformational impact on Oil Search and PNG

ExxonMobil quality operator

Foundation for major LNG industry in PNG

Seven fold increase in proven and probable reserves, increasing from 67 mmboe to 567 mmboe, with significant further potential upside

NPAT of US$133.7 million, US$99.6m excluding PNG Government back-in and tax adjustments. Satisfactory result given commodity environment, with average oil price down 35%

Strong balance sheet with US$1.3 billion cash at year end, totalliquidity of US$1.6 billion (including line of credit). Sufficient for both PNG LNG equity contribution plus funding of T3/T4 gas exploration/ appraisal programme

6

Outstanding Safety Performance

Total Recordable Incidents (TRIs) of 1.16 in 2009

TR

I /

1,0

00

,00

0 H

ou

rs

0

2

4

6

8

10

12

14

1998 1999 2000 2001 2002 2003 2004 2005 2007

Oil Search

2006

Australian Companies (APPEA)

2008

InternationalCompanies

(OGP)

12.7

9.1 9.37.8

7.0 7.3

5.2

9.4

8.26.3 6.8

3.9 3.1 2.9 2.7 2.1

4.0

3.6

4.9

5.76.0

2009

8.5

10.69.8 10.7

5.8

1.7

4.7

2.4 2.31 2.05 1.162.04

7

Consistent TSRperformance over 5 years

Source: IRESS

Relative TSR performance for period ending 31 December, 2009

ASX 100 Index Median Company OSH performance# Ranking based on ASX 100 composition at the beginning of the reference period.

-5

0

10

20

30

40

1 Year 3 Year 5 Year

% T

SR

per

an

nu

m

1st

3rd

OSH Ranking #

42nd

8

Future Value Growth

Driven by :- PNG LNG delivery Project optimisation Further LNG train development Reserve growth and exploration success

Comprehensive programmes to delivervalue through to PNG LNG first gas

9

PNG LNG Project

10

PNG LNG Project

World class LNG project under construction

Aligned joint venture ExxonMobil Operator –

excellent track record Supportive Government

and communities Provides infrastructure

for future growth Transformational for Oil

Search and PNG

11

PNG LNG Projectthe road to sanction

2008 Signed JOA, aligning JV partners in March Signed Gas Agreement with Govt in May Commenced FEED in May Commenced marketing discussions late 2008 Developed financing plan

2009 Submitted EIS in January Signed UBSA in May Signed HOAs Commenced early works EIS approved in October Completed FEED, LNG plant capacity

increased to 6.6 MTPA

12

PNG LNG Projectthe road to sanction

December 2009 Completed LBSAs Signed 3 SPAs with TEPCO, Osaka Gas and Sinopec Development approval 8 December 2009 EPC contracts awarded 9 December 2009 Financing documents signed 15 December 2009 with

ECAs, Commercial Banks and ExxonMobil for $14 billion –world’s largest project financing

Government offered and Project accepted all development licences

Government paid past costs for equity back-in to new development licences

March 2010 Signed final SPA with CPC – now fully contracted LNG vessel charter contracts signed with

Mitsui OSK Lines Minor legislation amendments 12 March – Financial Close

13

PNG LNG Project

Construction has commenced (roads, bridges, camps, site preparation and training facilities). First LNG sales expected 2014

First phase CAPEX, including FEED and early works estimated at US$15 billion

Contracts: LNG Plant: Chiyoda/JGC Offshore Pipeline Saipem Hides Gas Plant CBI/Clough JV Onshore Pipeline Spiecapag Infrastructure McConnell Dowell/CCC JV Early Works Clough/Curtain JV Associated Gas (OSH only) Aker Solutions

Mix of fixed price/variable price contracts Resourcing by contractors underway now Operator ExxonMobil has excellent record of

delivering projects on time, on budget

14

Proposed PNG LNG Future Activities

2010 2011 2012 2013 2014

FinancialClose

Continued early works.Detailed design.

Order long leads and place purchase orders.Opening supply routes.Contractor mobilisation.Commence AssociatedGas (AG) construction.

Pipe laying Kutubu to Hides.

Ongoing drilling.Complete Hides plant.Commission LNG plant

with Kutubu gas.

Ongoing procurement and mobilisation.

Airfield construction.Drilling mobilisation.

Offshore pipeline construction start.

Onshore line clearing.Start LNG equipment

installation.

First Gas from Train 1,

then Train 2

AG complete.Pipe laying

(Kutubu to Omati).Offshore pipe lay

complete.Start Hides plant

installation.

15

PNG LNG Ranking (Macquarie Equities)

Industry observers rank PNG LNG highly on returns

Source: Australian Energy Sector , Macquarie Equities Research, 12 January 2010

Qata

rGas3

PN

G L

NG

T3

Plu

to T

3

PN

G L

NG

T1

/T2

Po

seid

on

GLN

G T

2

Ich

thys

AP

LN

GT1

/T2

Wh

eats

ton

e

Su

nri

se

Go

rgo

n

GLN

G T

1

Bro

wse

Plu

to T

1

0

5

10

15

20

25

30

35

%

16

GasGrowth

17

PNG Gas Growth

Key strategic priority for Oil Search is to grow gas business in PNG

LNG remains optimum commercialisation route for additional gas

PNG LNG will provide infrastructure and capacity to facilitate expansion and provide excellent cost structure: Use of capacity in pipeline, jetty, tanks and services

Trained local work force

Government is supportive of future gas growth

Pace of gas growth will be determined by: Resource aggregation/exploration

Joint Venture alignment

Market access

18

Existing Gas Discoveries

PRL01

PPL234

PRL08PPL240

PRL03

PRL11

PDL7

PPL239

PDL1

PPL190

PPL219

PRL10

PRL02

PDL2

PDL4

PDL3

PRL09

PPL244

9°S

6°S

145°E50km

Kumul Terminal

PDL6PDL5

APRL14

PPL260

APPL249

APPL250

PPL

233

PDL9PDL8

142°E

Hides/Juha/Angore

Kutubu/Agogo/SEM

P’nyang

Pandora A

Uramu

Barikewa

Gobe/SEGElk/Antelope

Distribution of discovered 2P reserve/resource Significant discovered oil & gas reserves/resources

in Papuan Basin (predominantly in Fold Belt) Basin is predominantly gas prone 85% of basin’s resources by boe are gas

19

PNG Gas Growth Activities

Two largely independent core gas development streams: PNG LNG dedicated fields

Material core reserves Proven 300 mmboe (OSH share) sold Proven & probable 500 mmboe (OSH share) –

significant upside Field development optimisation Future appraisal Strong partner alignment

Other fields and exploration Material resources still to be commercialised Proven & probable 281 mmboe (OSH share) Future appraisal and exploration underway Developing material portfolio ex PNG LNG

Objective is to prove up sufficient proven contractible reserves to underwrite Trains 3 and 4

20

PNG Gas Growth Activities

Foldbelt/Highlands: Adjacent to PNG LNG upstream infrastructure Large structures, moderate risk, high OSH equity 2010 and 2011 activity:

− Drilling Korka− Barikewa seismic (completed) followed by appraisal drilling− Huria seismic− Mananda drilling

Gulf of Papua: Large under-explored areas with diverse licence holdings Planned 3D seismic will image subsurface, help high-grade

portfolio Opportunity to extend 3D survey into nearby licence 2010/2011 activity:

− 3D seismic survey− Drill Flinders− Appraise Pandora

Foreland and Strickland: Maintain watching position CBM test in 2010

21

Circle areas proportional to reserves potential

Outer circle unrisked potential, inner circle risked potential

Red =GasOrange= CondensateGreen = Oil

Proposed 2010/11 PNG Gas Exploration

PRL01

PPL234

PRL08PPL240

PRL03

PRL11

PDL7

PPL239

PDL1

PPL190

PPL219

PRL10

PRL02

PDL2

PDL4

PDL3

PRL09

PPL244

9°S

6°S

145°E50km

Kumul Terminal

PDL6PDL5

APRL14

PPL260

APPL249

APPL250

PPL

233

PDL9PDL8

Flinders

Barikewa Deep

Wasuma (PPL 219 & 190)

Cecilia West

KorkaHuria (PDL 8)

Mananda FW

Mananda Attic

142°E

22

PNG Offshore 3D Survey

4,700 km2 3D

4,700 km2 of 3D seismic to be acquired in 2010 – largest in PNG history

Gulf ofPapua

23

Operations

24

Oil Search Production

0

2

4

6

8

10

12

14

2004 2005 2006 2007 2008 2009

Net Production (mmboe)

11.05

12.17

10.219.76

8.608.12

7.2-7.4

2010

Kutubu

Moran

Gobe Main

SE Gobe

SEM

Hides GTE

MENA

(Forecast)

2525

2009 Production Performance

Excellent safety performance

2009 production of 8.12 mmboe Strong underlying performance

in all fields Two new rigs (103 and 104)

operating throughout year with significant performance improvements

Total cash costs (inc corporate costs, FX) of US$12.99/boe, down 7% from 2008Achieved despite 4%

reduction in saleable oil volumes and inflationary environment in PNG

Production impact of recent drilling at Usano

0

2,000

4,000

6,000

8,000

10,000

12,000

1992

1994

1996

1998

2000

2002

2004

2006

2009

Oil Rate (bopd)

Usano Main Block

Usano East Block

UDT 7

UDT 11

UDT 8,9

UDT 10,12

26

Oil development drilling continues to add value

Since 2003, gross PNG proven (1P) oil reserves have increased by51 mmbbl and proven and probable (2P) reserves by 37 mmbbl

Development drilling has added 2P reserves at average cost of US$11.72/bbl

Many further opportunities exist, including appraisal of Agogo deep (ADT 2), drilled in late 2009/10, recently tested at 2,000 bopd.Testing of discovery is ongoing

PNG Oil Fields – Gross Ultimate Recoverable Reserves (pre-LNG)

1P

2P

440

460

480

500

520

540

560

Mil

lio

ns

of

Barr

els

2003 2004 2005 2006 2007 2008 2009

2727

Reserves & Resources31 December 2009

Six-fold increase in proven (1P) reserves, from 50 mmboe at end 2008to 344 mmboe: PNG LNG Project reserve booking of 301 mmboe 2009 production of 8.1 mmboe Oil reserve additions at Kutubu, Gobe and SE Gobe of 2.4 mmboe

Seven-fold increase in proven & probable (2P) reserves, from 67 mmboe to 567 mmboe: PNG LNG Project reserve booking of 505 mmboe 2009 production of 8.1 mmboe Oil reserve additions at Kutubu, Gobe and SE Gobe of 2.8 mmboe

2C resources, comprising gas and associated liquids, of 281 mmboe at end 2009, compared to 886 mmboe at end 2008: Adjustment of 79 mmboe, due to Government back-in, to PNG LNG,

initial equity determination and field reserve changes PNG LNG Project reserves booking of 505 mmboe Decrease of 21 mmboe for revisions to certain fields’ 2C estimates

and Government back-in

Total 2P and 2C reserves and resources of 848 mmboe

2828

2010 Operations Outlook

Gas value driving revised Operating Framework:

Field reliability management

Gas conservation with minor oil production impact Value-adding PNG production activities will continue in

2010, including 1 – 2 wells at Moran, appraisal of Agogo ADT 2 deep play and workover campaign in Kutubu, Moran, SE Gobe

Ongoing focus on costs and capital efficiency following 2009 Operations Review

Aligning and maximising use of infrastructure to support LNG project

Production outlook for 2010 of 7.2 – 7.4 mmboe, with incremental activity expected to flatten decline curve in 2011 - 2013

2929

Exploration Outlook

PNG: Exploration for gas – key to driving LNG expansion Additional oil focused exploration in 2010:−Wasuma (25 mmbbl mean, currently drilling in PPL 219) −Mananda Attic (30 mmbbl mean in PPL 219, plus gas

play)

MENA: Focus on finding material oil and maximising asset

value:−Evaluate commerciality of Shakal (Kurdistan Region, Iraq) and

Tubb’a (Yemen) discoveries−Oil–focused drilling ongoing within Blocks 3 and 7 in Yemen,

targeting 3D-defined structures – encouraging signs in Al Meashar–1, Block 7

−Seismic in Kurdistan (Block K42 in world class exploration province) and Tunisia planned to define drillable large structures

30

PNG 2010 Exploration Summary

PRL01

PPL234

PRL08PPL240

PRL03

PRL11

PDL7

PPL239

PDL1

PPL190

PPL219

PRL10

PRL02

PDL2

PDL4

PDL3

PRL09

PPL244

142°E

9°S

6°S

145°E50km

Kumul Terminal

PDL6PDL5

APRL14

PPL260

APPL249

APPL250

PPL

233

PDL9PDL8

Commitment

Discretionary

Future Commitment

Well Types

Prospect/Lead (POS%)Mean Oil Gross (mmstb)Mean Gas Gross (bscf)

Seismic

CommitmentDiscretionary

Permit 2D(distance)/3D(area)

Flinders (12.5%)1.0 tcf+

Korka (15%)1.3 tcf +

Mananda Attic (45%)30 mmstb

Mananda FW (10%)1.2 tcf +

PPL 234 3000+km2

PRL11 80km

PPL233 55km

PDL2 100km

Wasuma HW(30%)25 mmstb

Wasuma Deep (20%)25 mmstb

31

MENA 2010 Exploration Activity Summary

Sana’a Office

Dubai Office

Commitment

Discretionary

Future Commitment

Well Types

Prospect/Lead (POS%)Mean Oil Gross (mmstb)Mean Gas Gross (bscf)

Seismic

CommitmentDiscretionary

Permit 2D(distance)/3D(area)

Tajerouine

Le Kef

K42

Shakal

Block 7

Block 3

Taj. + Le Kef 600km

K42 200km

Shakal 50km

Jebel Milh (17%)28 mmstb

Block 3 & 7 400km

Al Measher (20%)20 mmstb

Block 3/7 well,late 2010

32

Outlook and Summary

33

Outlook and Summary

Oil Search’s core business in excellent shape to drive further value growth over next 3 years

PNG LNG Project construction underway ExxonMobil quality operator for delivery

Contractors mobilising

Buyers secured, with pricing locked in

Finance secured, excellent package

Significant impact on PNG already being felt

PNG LNG is country and Company transformational

34

OSH good value on 1P reserves relative to Global Energy Sector

0

5

10

15

20

25

30

35

40A

rro

w

Hu

sky

Mu

rph

y

BG

Mara

thon

Rep

sol

Woo

dsi

de

EN

I

Ch

evro

n

An

ad

ark

o

Sh

ell

Hess

Talism

an

Ap

ach

e

Devo

n

San

tos

Oil

Searc

h

Exxo

nM

ob

i

To

tal

BP

Ph

illip

s

Note: Enterprise Values as at 31 January, 2010. 1P reserves based on latest publicly available reserves figures

Source: Public information

Enterprise value (US$m) / 1P reserves (mmboe)

35

Significant additional LNG Reserve Booking Potential

Sanction of PNG LNG has delivered incremental reserves of 301 mmboe and 505 mmboe on 1P and 2P basis respectively

Additional net 2C resources of 281 mmboe in other OSH fields

Total resources in OSH and other PNG fields (ex PNG LNG) estimated at 1,686 mmboe (9 tcf)

PNG 2009Reserves & Resources (100% Licence Estimates)

-

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

Mil

lio

ns

of

Barr

els

Oil

Eq

uiv

.

Oil Only Oil + PNG LNGOSH Fields'Reserves &Resources

All OtherResources

2P/2C

Oil Search 2009PNG Fields Net Reserves & Resources

0

100

200

300

400

500

600

700

800

900

Mil

lio

ns

of

Barr

els

Oil

Eq

uiv

. (N

ET

)

Oil Fields Oil + PNG LNG Oil + PNG LNG +Resources

1P/1C 2P/2C

36

Active programmes to deliver in 2010

Field and development optimisation (Central Foldbelt)

Seismic acquisition and drilling

Accelerated exploration (NW Foldbelt and Gulf)

Seismic and drilling, CSM

Selected acquisitions (PRL 1, PPL 244 and others)

Partner alignment (PNG LNG and others)

37

OSH has financial capacity:

US$1.29 billion in cash at end December

US$362.5 million available from term revolving facility, nil drawn down

Group liquidity ~US$1.65 billion

Sanction of PNG LNG Project in December delivered US$88 million net to OSH from PNG Government back-in to Project gas licences

Claw-back from lenders of 70% of Project costs spent prior to Financial Close will deliver ~US$300 million inflow in late March

Strong balance sheet

38

2010 Guidance Summary

Production: 7.2 – 7.4 mmboe. Incremental activity in 2011 – 2013

expected to flatten decline curve Opex:

US$16-18/boe Increase due to FX, PNG inflation, increased spend to

improve reliability & extend life and relatively fixed cost base on lower production. In addition, accelerated focus on workovers to maximise oil recovery prior to gas blow down

Likely to stabilise/decline in 2011 D,D & A:

US$6-8/boe Decrease due to recognition of LNG reserves

Capex: Exploration – US$210m (80% in PNG, 20% in MENA) Production/Other – US$85m (inc corporate & other gas) PNG LNG – US$1,000 - 1,350m (inc capitalised interest &

upfront fees)

39

Production Outlook

PNG LNG adds ~18 mmboe pa to OSH at plateau in 2015 onwards. 30 year Project life

T3 could add an additional ~9 mmboe pa, with T4 of similar magnitude

Net

Pro

du

ctio

n (

bo

ep

d)

0

10,000

20,000

30,000

40,000

50,000

60,000

2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025

LNG GasLNG Gas

PNG DevelopmentPNG Development

70,000

80,000

Potential T3 LNG GasPotential T3 LNG Gas

LNG CondensateLNG Condensate

90,000

Potential T3 LNG CondensatePotential T3 LNG Condensate

40

Summary

Primary focus in 2010/2011 on proving up sufficient contractible gas to underwrite T3/T4

Core oil production remains solid. Focus on life extension, reliability and gas conservation A new value equation

Measured oil exploration in PNG and MENA

Activities underwritten by strong balance sheet, with sufficient liquidity to meet PNG LNG obligations, T3/T4 appraisal and exploration activity

41

Port Moresby144°E

6°S

146°E142°E

Appendix 1. PNG Attracting Growing Interest

PNG transaction value ~US$1.4 billion over past 18 months, inc NOEX acquisition of AGL licences

Talisman and Sasol have acquired significant acreage in Western Forelands. Interoil has strong position in Eastern Forelands

OSH strategy focused on enhancing position in core PNG LNG Foldbelt acreage and Gulf -viewed as offering greatest potential for large gas discoveries

Sasol & Interoil Equity Participation

80km

8°S

Port Moresby144°E

8°S

6°S

146°E142°E

Talisman Equity Participation

80km

Juha

Gobe

Kutubu & Agogo

Hides & AngoreJuha

Gobe

Kutubu & Agogo

Hides & Angore

Port Moresby144°E

8°S

146°E142°E

Petroleum Licences

CSG Licences

6°S

80km

Oil Search Equity Participation

Juha

Gobe

Kutubu & Agogo

Hides & Angore

42

Appendix 2. Papuan Basin Major Areas – OSH assessment

NW Fold BeltLarge undrilled surface anticlines remain

Low risk on reservoir, charge and seal

StricklandA number of undrilled small low risk prospects and leads are present.

Poor quality seismic

Southern ForelandA number of risky small undrilled prospects and leads remain

Poor quality seismic Gulf of PapuaA number of prospects and leads across varied play fairways

Prospects can be quickly de-risked with 3D seismic

Aure Fold BeltArea is under explored –Elk indicates significant potential for carbonate plays and emerging play potential

Key risk is reservoir effectiveness

Interior Fold BeltNumerous oil & gas seeps indicate a working hydrocarbon system

Central Fold BeltOnly proven oil prone area.

Significant subthrustpotential exists

8°S

142°E 144°E

100km