Abstract: Transmission line is one of the most important lifelines. It often crosses a long transmission distance and covers a wide range. Along the transmission line the environmet significantly varies; the geomorphological and geological conditions are complext, w,which makes the transmission line is threaten by geological hazards. Especially in recent years, affected by extreme climate, the geological hazards along the important transmission lines appear to be of high-frequency. The situation of hazards prevention and control is severe. In order to guarantee the safe operation of massive power grid in extereme environment, the geological hazards risk assement of important transmission lines is urgently needed. In this paper the selected indices include:slope, aspect, slope length, curvature, cutting depth, road buffering, river buffering, surface roughness, surface deformation, surface moisture content etc. By using the contribution weight model to evaluate the geological hazard of the typical transmission channel named Lu Mao line. The results show that,(1)the most contribution rate of geological hazards is aspect, then slope, river buffering, road buffering and so on. (2)The whole transmission channel is mainly in the lower hazard area and the moderate hazard area, and the area accounts for 58.22% of the whole area. (3)From the low risk area to the high hazard area the disaster distribution density gradually increases, from no disaster to 0.536/km². And the hazard degree of each pole tower was analyzed and evaluated.