Amphibious tricycle

The amphibious tricycle contains front wheel, fork, steering control mechanism, back wheels, clutch, propeller and sealed carriage. It has also main chain wheel and gear rack installed on the vertical fixed shaft in the back part, two subsidiary chain wheels in the front part and connected to the main chain wheel via chains, saddle in the middle part, slide rails on two sides, pedals on the slide rails and connected to chains in the same side, driving pipe sleeved on the back wheel shaft fixed to the bottom and connected via the clutch to the shaft, two ratchet wheels on the driving pipe and meshed to the gear rack and conic gear on the propeller and connected to the driving pipe via clutches and other parts. The present invention has lower gravitation center and high stability.