Abstract: A novel in-pipe inspection robot system is presented.Video signals of the object in the pipe can be recognized and judged by the video crossing line,and the poisonous gas remained in the pipe can be recognized and judged by the gas sensor.The two kinds of judgment results are merged and input into the control system to control the robot to achieve corresponding motion and actions.The mechanical structure of the robot enable it to move in horizontal,vertical as well as curved pipes to carry out inspection tasks simply,quickly and accurately.The experiment with the prototype proves the feasibility of the whole system.