Abstract: The walking wheel introduced here is a new invention of runing gear for soft ground vehicles or paddy field tractors. It has won a gold award at the International Invention Exhibition, Montreal, Canada, on November 29th, 1987. A prominent feature of the walking wheel is that it is able to keep the height of wheel centre at a constant distance to the ground by retractable legs during the period of each leg contacting and leaving the ground surface. Through using this kind of walking wheel, vehicles working on the soft soil can be assured to increase driving force, and decrease rolling resistance, so as to increase tractive efficiency of the vehicle, also, vehicles with the walking wheel can move smoothly on hard surface road.This paper analized detail kinamatic and characteristics of the walking wheel,derived the equations of motion locus of the wheel foot tip, motion velocity of the wheel centre, acting force on elements , and the momental and efficiency of the whole wheel. All of these are essential for optimizing parameters and to develop and design a reasonable structure of the walking wheel.