Rising oil prices drove the result, with Petrochina's realised oil price reaching US$26 a barrel, an increase of 10.1% from the previous year's US$23.61 a barrel.

Mainland oil producers have benefited from a global oil price increase earlier this year brought about by the Iraq war. Rival companies China Petroleum and Chemical Corp earlier this week posted a 97 per cent jump in their net income to US$1.3 billion for the first half.

PetroChina's increased interim earnings were also boosted by a turnaround of its once distressed chemicals business, which posted an operating profit of US$78.3 million. The company's refining business posted a US$180 million operating profit, more than double from the year-earlier period as it processed more oil and sold more petrol, diesel and kerosene.