Rotating shaft milling square clamp

The invention belongs to the technical field of clamps, and particularly relates to a rotating shaft milling square clamp which comprises a clamp body, the outer surface, away from a rotating shaft body, of the clamp body is in threaded connection with a fastening screw, the fastening screw is in threaded connection with an open pressing plate through a screw hole, and the lower portion of the open pressing plate is clamped to the outer surface of the rotating shaft body. Indexing chucks are arranged at the two ends of the rotating shaft body, four key grooves are evenly formed in the outer surfaces of the indexing chucks at intervals, the middle of the side face, away from the indexing chucks, of the high-pressure air box is slidably connected with one end of a sliding cylinder in a sleeved mode, and the other end of the sliding cylinder is connected with the outer surface of the rotating shaft body in an attached mode. The vertical side face of the clamp body is evenly provided with containing grooves at in