Based on hydraulic model test,the properties of water diversion and sediment control of Tongzilin hydropower station in Yalong River under different top elevations of sand trap,various operation and opening gate for sediment release are studied and the effective suggestions for the requirement of water diversion and sediment control is proposed.The experiments show that,to take reasonable and effective operations plans or open gate for sediment release can achieve a good flow guiding and sediment control effect and meet the requirements of the design.