Flow field information is very important to study hydro-performance of amphibious vehicle. However, it is difficult and expensive to measure it. To overcome the problem, CFD was used to acquire the information. The Reynolds Average Navier-Stokes equation was taken as basic mathematical model to describe flow field. Flow field region was discretized by hybrid mesh and governing equations were discretized by Finite Volume Method. Second order upwind scheme was used for spatial discretization and Euler scheme was used for temporal discretization. Result indicates that simulated flow field is consistent with experimental flow field on shape and hydrodynamic characteristic. Resistance accuracy is nearly 12%. It can be concluded that the method based on CFD is feasible to simulate the flow field around amphibious vehicle.