In order to investigate the cavitation phenomenon of the hydraulic cone valve, the magnitude of radial offset was calculated by the fluid mechanic theory and the radial force analysis of the fluid on the valve core. The solid models of the internal flow field were established by UG. The mesh was divided by using ICEM-CFD software. The numerical simulation of the two-phase flow was performed on the cavitation of the flow field inside the cone valve based on FLUENT. The variation on cavitation was obtained under four factors, such as radial offset, half cone angle, opening degree and back pressure. A visible experiment of the cone valve cavitation was built. A high pixel camera was used to capture the cavitation image of each valve position. According to the experiment results, the simulation results were verified. The results show that the radial offset causes the cavitation position accumulated in the valve cavity on the side of the upper cone. In addition, the strength of the cavitation changes slowly with the half cone angle of 45°. At the same time, when the half cone angle is 45°, and the opening degree is 0.4mm, the strength of cavitation is the most obvious. With the increase of the opening degree, the strength of air mass in the cavitation phenomenon gradually weakens. Combined with the flow capacity and cavitation strength, the half cone angle of 45° is suitable for cone valve. Furthermore, the increasing of the opening degree and back pressure in a reasonable range can effectively suppress cavitation.