The present invention belongs to the technical field of robot obstacle avoidance path selection and optimization control and relates to a 3D live-action map and electronic compass-based inspection robot path optimization controller and a control method thereof. According to the method, a two-dimensional positioning coordinate system of a transformer substation main control chamber is formed based on a 3D live-action map and the electronic compass positioning technology. Meanwhile, combined with an intelligent inspection robot obstacle detection system of a power station main control chamber, the data of the above systems are dynamically compared, and then the marching path of the robot is calculated and optimized. Therefore, the path is dynamically adapted to the change of the surrounding operation environment of the robot in real time. The problem in the prior art that a transformer substation inspection robot cannot automatically adjust the operation path itself in real time for the changeable environment of the transformer substation main control chamber is solved. Therefore, the path can be dynamically adapted to the change of the operation environment of the inspection robot.