BEIJING, July 18 (Xinhua) -- Chinese shares gained for the first time in four days on Friday, boosted by lower world crude oil prices and an overnight growth on the Wall Street.

The benchmark Shanghai Composite Index was up 3.49 percent, or 93.59 points to end at 2,778.37 points. The Shenzhen Component Index closed at 9,588.40 points, up 3.23 percent.

Aggregate turnover on the two bourses totaled 89 billion yuan (13.05 billion U.S. dollars).

Oil refiners and airlines benefited from the falling world crude oil prices, leading the rise.

Airline shares rose across the board. Air China, the country's flag carrier, was up 6.45 percent to 10.40 yuan. China Southern Airlines rose 8.66 percent to 8.16 yuan and China Eastern Airlines grew 5.56 percent to 7.40 yuan.

Sinopec, Asia's top oil refiner, surged 7.57 percent to 11.09 yuan despite a 50 percent decrease in its first-half profit forecast. PetroChina, the country's largest oil producer, added 2.04 percent to 15.02 yuan.

Finance shares regained some lost ground on prospects of favorable policies at the central economic conference, which would kick off this weekend according to early reports, a Pingan Securities analyst said.

The Industrial and Commercial Bank of China (ICBC), the country's largest lender, rose 2.73 percent to 4.90 yuan. China Life, the country's leading insurer, gained 8.28 percent to 25.90 yuan.

Source: Xinhua