According to the some problems existed in the unmanned vehicle, a new amphibious hydrofoil vehicle with variable shape was proposed based on the characteristics of the torpedo and hydrofoil in this paper. The hydrodynamic characteristics of the amphibious hydrofoil vehicle is numerical simulated based on the LBM-LES. Lift curves and drag curves of the amphibious hydrofoil vehicle under water and surface of the water are got. The comparison results shows that the vehicle retracts its hydrofoil to make the drag smaller in a small angle of attack under water, it suitable for high speed navigation. The vehicle unfolds the hydrofoil to increase lift and reduce drag on the surface of the water. Meanwhile, the amphibious hydrofoil vehicle can meet its requirements of navigation under water and on the surface of the water by changing its shape. Shape design and amphibious navigation performance of vehicle still have much room for optimization.