The development of a novel amphibian walking robot prototype is proposed according to the need of duty under bad circumstance. It can be used as the carrier of the reconnaissance equipment, the weapon system and the communication system, and complete many kinds of missions in the place near the sea and tideland which a man can not complete. Some new dynamics questions is introduced because of multi-leg structure features and functionality of the amphibious. The integrated approach of series parallel is proposed to solve the characteristic that swing and supporting phase are appeared respectively during walking. Hydrodynamic effect is also considered in our dynamics equation. At last, the least distribution model of driving moment and driving energy of robot are set up in this paper. These conclusions have very important effects to the control of robots.