Abstract: With the foundation and improvement of market economy in China, particularly, since CNPC coming into the stock market, the reserve conception is changing from geologic reserve to remaining economic recoverable reserve. The most important thing is to emphasize the effect of economic factors on reserve evaluation. This paper, based on some cases, analyzes the effect of economic factors such as oil prize, cost, tax and investment on reserve evaluation during the process of reserve evaluation according to the SEC criterion. It is concluded that oil prize is the most effective factor on the evaluation results, the cost and the tax are in the next place.

Key words: reserve, evaluation, economic factor, effect, influence