Because the risk factors for oil and gas transmission pipeline have complexity and fuzziness, and the factor weights are difficult to distribute. Therefore the entropy weight method was used to determine the factor weights, and the fuzzy comprehensive was used to evaluate the risk. First of all, the basic principle of entropy weight method and steps of fuzzy comprehensive evaluation method were briefly described. Then a section of oil conveying pipeline in Beijing area as an example, the risk evaluation index system was established and the factors weights were determined by using the entropy weight method. Finally, the risk level was determined by using the fuzzy comprehensive evaluation method, and the result was consistent with the judgment made by field experts. And according to the evaluation results, the corresponding prevention measures were proposed, so as to verify the feasibility of the method.