Abstract: Currently, in the field of in-situ leaching uranium mining, the traditional well washing process suffers from low effective operating pressure at the well bottom, making it difficult to clean fouling deposits in underground filter sections. To address this, research is conducted on high-pressure cavitation jet well washing technology to enhance the efficiency of borehole scale cleaning. By designing and optimizing the structural dimensions of the cavitation jet well washing nozzle, the performance of jets under different nozzle combinations with four levels and five factors is simulated using Fluent software. Parameters such as jet impact force and gas-phase volume fraction are compared to select the optimal nozzle configuration. The results indicate that for well washing operations in in-situ leaching processes, the optimal nozzle dimensions are: an inlet nozzle diameter of 4.17 mm, an inlet flow channel length of 10 mm, an inlet fillet radius of 1.0 mm, a cavity diameter of 13.75 mm, a cavity length of 5 mm, a collision wall angle of 60°, an outlet flow channel length of 5.05 mm, and an outlet nozzle diameter of 5 mm. Laboratory tests demonstrate that under fixed cleaning time with a rotary cavitation well washer, a cleaning zone becomes apparent at a pressure of 10 MPa. These findings provide a reference for high-pressure cavitation jet well washing operations in in-situ leaching.