The invention relates to a method for drawing a lightning risk rating scheme of a power transmission line. According to the method, the fault of the power transmission line is monitored in the onlinemanner through a distributed fault diagnosis system of the power transmission line. The terminal of the distributed fault diagnosis system of the power transmission line is directly installed on the body of the power transmission line and is used for diagnosing and positioning the fault of the power transmission line. After that, according to the positioning result of the fault of the power transmission line, a lightning disaster event on the body of the power transmission line is analyzed. The lightning risk rating scheme of the power transmission line is obtained in combination with variousfactors and according to a preset rule. As a result, the assessment for the lightning risk level of the power transmission line is realized. Compared with the prior art, the method disclosed by the invention is more comprehensive in combination factor, and capable of effectively distinguishing the advantages of direct lightning, lightning induction and the like.