Abstract: For a Kaplan turbine, the difference of blade geometry may impact the operating performance and operating range of the turbine. Therefore, the relationship between the different shapes of blade leading edge and the turbine performance parameters was studied in this paper. Based on the same blade setting angle, a numerical simulation for the model Kaplan turbine was conducted under the situation of three types of blade leading edge shapes. The results showed that: at the condition of the same blade setting angle, the different blade leading edge shapes could regulate the flow rates and change the distribution of circular rector in the flow passage. It is also helpful to improve the pressure distribution on pressure and suction sides of the blade and to decrease the low pressure area in the runner; these will improve the efficiency and cavitation performance, the different leading edge shape of the blade may adjust the operation scope. This study can provide a theoretical guidance to the optimal design of the turbine.