Fluid jet polishing is a new precision optical machining method. The application of multiple nozzle structure and rectangular nozzle structure can effectively improve the polishing efficiency. Impact angle affects the hydrodynamic characteristics of impingement, which has an important influence on material removal and polishing effect. Therefore it is necessary to further analyze the flow field distribution characteristics of different nozzle structures with different impact angles. The circular single nozzle jet model, multi-nozzle and rectangular nozzle jet model with different impact angles are built. Based on the fluid mechanics theory, the oblique impingement process of different nozzle structure jets is numerical simulated by FLUENT, and the fluid jet velocity and pressure distribution curves on the workpiece wall have been obtained.