The invention discloses a multi-sensor information fusion power transmission line robot navigation method and a multi-sensor information fusion power transmission line robot navigation system. The method comprises the following steps: collecting the video image information of a power transmission line in the advancing direction of a power transmission line robot through a visual sensor, and extracting the hierarchical gradient direction histogram features in the video image information; inputting the extracted hierarchical gradient direction histogram features into a classification model trained by using a support vector machine for classification, and determining the type of an obstacle; a binocular vision system, one or more groups of ultrasonic sensors and one or more groups of photoelectric sensors are respectively used for simultaneously positioning obstacles to obtain multiple groups of obstacle positioning information; and fusing the acquired multiple groups of obstacle positioning information through a neural network to obtain a final positioning result of the obstacle in the advancing direction of the power transmission line robot. According to the power transmission linerobot navigation method, various sensor information is combined, the problems that a traditional positioning method is limited in detection range and small in sensing information amount are solved, and the anti-interference capacity of a navigation system is enhanced through comprehensive processing of the multi-sensor information.