The invention discloses an ROS-based transformer substation inspection robot system and method. The ROS-based transformer substation inspection robot system comprises a bottom hardware part, an uppercontrol part and an environment sensing module. The bottom hardware part comprises a motion control module, and the motion control module is packaged into a motion control ROS node and used for collecting motion information of a robot and receiving a motion instruction of the upper control part to control motion of the robot. The environment sensing module is packaged into an environment sensing ROS node and used for collecting internal environment information of a transformer substation where the robot is located. The upper control part comprises a map building module. The map building moduleis packaged into a map building ROS node. The image building ROS node, the motion control ROS node and the environment sensing ROS node conduct mutual communication. The map building ROS node is usedfor building an internal running environment map of the robot transformer substation according to the motion information of the robot and the internal environment information to the transformer substation.