To provide an amphibious vehicle, which has a large vertical stroke of wheels and can retract a screw during land traveling, and which, on water, can stably travel while retracting wheels, maintain a horizontal attitude and prevent the screw from breaking even in collision with rocks at the water's edge.

The amphibious vehicle includes a combination of a trailing arm suspension assembled with a driving mechanism and an air suspension system using a dual rod type differential cylinder, which can develop an alternative function to a bump stop necessary upon extending or retracting wheels or when the vehicle bounds, a buoyancy assisting system using a tire house of the vehicle body, and a retractable screw, for enabling the purpose.