The fir tree tenon groove of the power turbine disk of the gas turbine is formed by broaching,and most of the tenon groove allowance is carried out in the rough broaching process. Because the workpiece material is high-temperature alloy,which with high strength and more allowance is removed at the same time,so it is easy to produce broach damage and collapse during rough broaching. In order to solve the failure of the rough broach,a practical grinding methods was put forward. Through the analysis of the temperature field during rough broach grinding,the process parameters of broach grinding were determined without being burned; the grinding wheel type,the cutting fluid type and the final grinding method were determined by using the grinding parameters of the rough broach.The results show that by using the method,the grinding quality of rough broach can be guaranteed. The research results provide reference for broach grinding.