Based on the design methods of fish friendly hydraulic turbines at home and abroad and traditional hydraulic turbines, this paper designs an axial flow fish friendly hydraulic turbine in plateau area by using Unigraphics NX. The steady-state simulation of the turbine is carried out by fluent, and the energy characteristics of the three blade runner are analyzed. Through the transient computation, the pressure fluctuation characteristics in the leafless area of the turbine with guide vane opening of 18.2° and 14.2° are studied, and the fish passing characteristics are analyzed. Compared with the evaluation criteria of fish friendly water turbine, the variation rate of pressure obtained is less than 550.3kpa/s, which meets the design criteria of fish friendly water turbine and basically meets the demand of fish passing down the dam.