The utility model discloses a GIS equipment partial discharge detector ultrasonic sensor fixing device, including insulator spindle and supersound fixed plate, the supersound fixed plate sets up in the top of insulator spindle, the supersound fixed plate includes supersound regulating plate and supersound elasticity post, supersound elasticity post symmetry sets up on the border of supersound regulating plate, supersound elasticity post constitution is used for the fixed frame of fixed ultrasonic sensor, the supersound regulating plate is provided with the sealing strip all around. The utilitymodel provides a fixing device is used for fixed ultrasonic sensor, can adjust according to the size of sensor to can fix not unidimensional sensor on this device, make it laminate on the pipe wall totally, thereby improve test data's accuracy, promote work efficiency.