The cavitation hydrodynamic performance of a pump-jet propeller was calculated and analyzed with the mixture homogeneous flow cavitation model based on Rayleigh-Plesset equations and sliding mesh. The effects of different rotational speed, cavitation number and flow velocity on cavitation characteristics of the pump-jet were studied. When the cavitation occurred on the blades, the propeller thrust and torque decreased significantly, thereby causing an open water efficiency decrease of 15%. For the same cavitation number, as the rotational speed increased, the pump-jet propeller blade cavitation phenomenon was more obvious. While for the same rotational speed, the smaller the number of cavitation, the- more remarkable the cavitation phenomenon was. However, when the cavitation number was greater than a certain value, the blade cavitation phenomenon disappeared.