Fuzzy weighting technique is carried out and applied to motion control of an amphibious hovercraft to resolve the motion control problem with navigation characteristic change greatly. Multiple models are constituted to cover the navigation characteristic variety bring by ship speed change. Controllers are designed for every speed point respectively, and fuzzy rules figure out controller weight to realize smooth switch between these controllers. Simulation tests show that, when speed of amphibious hovercraft changes in wide range, the controller designed based on fuzzy weighting has good performance in motion control. And the method will not bring controller's output jump, which is exist in general switch control.