Abstract： The virtual disk (VD) and overset (OS) models had been applied to the numerical simulation of impeller in waterjet which was installed on ship model in order to build numerical model for selfpropulsion test. Research and discussions were mainly concentrated on the axial velocity distribution of hull flow field and internal flow field, and the flow field characteristics of waterjet propelled ship were analyzed. The results revealed that the hull flow field coincided with each other for two models, but there was obvious difference in the internal flow field. Compared with the VD model, the OS model is more applicable to the actual state of the impeller. Both calculating models simulated the flow field characteristics of waterjet propelled ship well. There was significant consistency both in the regularities of local pressure distribution and wave jamming effect caused by jet steam.