Fixing clamp for machining

The utility model relates to the technical field of part clamps, in particular to a fixing clamp for machining, which comprises a base, a mounting rail fixedly connected to the top of the base, two sliding plates connected to the mounting rail in a sliding manner, and a clamping device, the two supporting plates are fixedly connected to the tops of the two sliding plates correspondingly; the movable plate can be pulled by hands to move out of the groove, meanwhile, the movable plate moves to drive the telescopic rod to extend until the top end of the telescopic rod moves out of the groove, the telescopic rod extends to drive the reset spring to extend and generate elastic deformation, then the movable plate is rotated to drive the clamping plate and the V-shaped clamp to exchange positions, and the movable plate is loosened. The reset spring in the stretching state drives the telescopic rod and the movable plate to reset, the movable plate enters the groove, the clamping plate can clamp the square part, the V