Amphibious vehicle plays an important role in modern equipment,and the existing heat dissipation system of amphibious vehicle underwater power system is difficult to meet the heat dissipation requirements of sailing in the water.A heat pipe heat dissipation system for amphibious vehicle underwater power system was designed,and the working condition of the heat pipe heat dissipation system was simulated and analyzed through Fluent.Relative experiment test was made.The results show that the designed heat pipe heat dissipation system can meet the heat dissipation requirements of amphibious vehicle underwater power system in underwater driving condition.