The invention provides a novel efficient amphibian vehicle; two propelling devices at the rear end are of same structure and each includes a steering engine arranged in the vehicle, an inner disc connected with the output end of the steering engine, an outer disc arranged at the outer side of the inner disc, spokes, and a tire, the inner disc is provided with three inner disc spindles arranged evenly, the outer disc is provided with three outer disc sliding shafts arranged evenly, each spoke is of circular structure composed of three sub-hubs, the tire is also of circular structure composed of three sub-tires, the sub-hubs and the sub-tires form a deformable wheel, one end of each sub-hub is hinged to the corresponding inner disc spindle, the other end of the each sub-hub is connected to the corresponding sub-tire, each sub-hub is provided with a curvilinear shaft slot, and the corresponding outer disc sliding shaft is arranged in each curvilinear shaft slot. Through simple mechanical transmission, expected motion trajectories of the propelling devices are achieved; the novel efficient amphibian vehicle is easy to control.