Positioning clamp for guide rail installation

The utility model provides a positioning clamp for installing a guide rail. The positioning clamp comprises a positioning base body, a fixing plate and a locking piece. The positioning base body comprises a base and a distance limiting seat, the distance limiting seat is arranged in the center of the lower portion of the base, and the length of the distance limiting seat is smaller than that of the base; the fixing plates are arranged on the left side and the right side of the base correspondingly, and a guide rail mounting cavity is defined by the fixing plates, the base and the distance limiting base. The locking piece is arranged on the fixing plate, the output end of the locking piece can penetrate through the fixing plate and is inserted into the guide rail mounting cavity, and the guide rail is pressed towards the side face direction of the distance limiting seat, the guide rail can be prevented from being moved and measured for many times, operation is easy and convenient, efficiency is high, and the d