Abstract: Due to the high head of the Pelton turbine, the high-speed jet causes very serious sediment wear to the turbine bucket. In order to explore the wear of sediment particles on the bucket of Pelton turbine under high-speed water flow, the liquid-gas-solid three-phase flow numerical calculation and sediment wear prediction of the bucket were carried out based on CFD technology for the whole flow field of Pelton turbine of Jiniu Hydropower Station, and the internal flow characteristics and sediment wear of a runner bucket were obtained. The results show that the trailing edge at the root of the bucket, the leading face of the bucket near the root as well as the notch and the splitter are severely eroded. The wear of the splitter and the notch is greater than that of the working face of the bucket. The wear rate from the splitter to the trailing edge generally increases first and then decreases. The calculated results of bucket wear are in good agreement with the measured results, and the calculated results are only about 6% larger than the measured results, which shows that the method of sediment wear prediction is effective and feasible. This study provides a technical method and basis for sediment wear prediction of Pelton turbine and operation and maintenance of power station.