In view of the difficult problem of robotic climbing,a new mobile system design plan of deformable wheel climbing obstacle-surmounting robot is proposed. According to the force analysis of the deformable wheels,the robot motion model is constructed and the model is solved by geometric relation. Combining with the shape of the common obstacles,such as staircase,the comprehensive scale of the deformable wheel climbing obstacle-surmounting robot is analyzed. And the robot can realize the switch of the circle wheels and deformable wheels. Finally,a prototype test is made successfully. The result of the test shows that the deformable wheel of the robot has high motility and strong crossing obstacle ability,and the robot can adapt to a variety of complex road conditions.