In this paper, a wheel/track mobil platform for robot search and rescue such dangerous tasks is designed. Through the wheel/track transform mechanism, the wheel and track motion modes can be switched alternatively to adapt to different ground situations. The friction between the belt wheel and hub is used to drive the track and its guide wheel is the one of the transform mechanism. When the guide wheel is retracted back into the hub, the track can automatically rebound back to wheel and wrap on the hub. Field experiments demonstrate that the designed platform can move on different ground surfaces.