The invention discloses an aerodynamic device and an aerodynamic automobile applying the aerodynamic devices. The defects that work continuity is low and a complete pollution-free effect cannot be achieved in the prior art are overcome. The aerodynamic automobile comprises an automobile body provided with an air storage tank, an air motor and the aerodynamic devices. Each aerodynamic device comprises an air disc located in the center position of a tire. Aerodynamic pumps are fixed to hubs of the automobile body. The air discs are connected with the aerodynamic pumps. The aerodynamic pumps, theair discs and the air storage tank are connected and communicate. The outer ends of plungers of multiple air cylinders of the aerodynamic pumps extend out of the tires. The air motor drives the tiresto rotate. Under the gravity of the automobile and the ground counteracting force, the plungers are pressed to act, and the automobile travels and is inflated with air serving as a power source at the same time. The aerodynamic automobile has the beneficial effects of being free of emission and pollution, long in working time, capable of obtaining energy conveniently and wide in market prospect.