The invention relates to the technical field of robots, and more particularly relates to a mobile robot planning method based on visibility graph guidance. A planning guidance area is established by using a visibility graph method to limit the expansion of a rapid random expansion tree (RTT), a generation shape of a random tree is constrained by establishing a vehicle kinematic model, meanwhile the generation of the random tree is accelerated by using a 8 nearest neighbor node search method, after the random tree is obtained, a path conforming to a mobile robot motion law is obtained by calculation, and finally, the path is optimized to improve the quality of the path. In the traditional fast random expansion tree planning algorithm, the planned path cannot meet the kinematic constraints of a wheeled robot, and meanwhile, as the structure of the random tree becomes larger, the generation efficiency of the random tree is low. Therefore, kinematic modeling is performed on an unmanned vehicle, and then the random tree conforming to the kinematic model of the unmanned vehicle is obtained within a short time in combination with the 8 nearest neighbor node search method, and an optimal path from a starting point to an end point is obtained through path optimization.