Abstract: Considering the hydrodynamic cavitation intensity and pumping liquid, based on a single-stage single-suction centrifugal pump with specific speed of 117.3, a new type of rotational hydrodynamic cavitation generator was designed. The CFX software was used to analyze the cavitation pattern and the law of cavities evolution of the rotational hydrodynamic cavitation generator. The results show that the cavitation groups of the rotational hydrodynamic cavitation generator can enlarge with decreasing inlet pressure and increasing flow rate. The cavities initiate around barricades and the tongue, the cavities in rotator initiate at the side of barricades and fall off behand the barricades close to tongue, the cavities near tongue fall off at the same time with the vapors behand barricades, however, they have different collapse periods. This novel rotational hydrodynamic cavitation generator improves the level of integration and has good cavitation effect and high head. The study of cavitation characteristics can provide a reference for hydrodynamic cavitation generator design.