The invention discloses a prestressed concrete tubular pile locking mechanical quick joint, and relates to a building concrete tubular pile connecting structure. Step conical holes are formed on inner holes of two ends of tubular piles; the quick joint is provided with a connecting device, and the connecting device consists of two cone expanding rings, two cone expanding plugs, two sets of fan-shaped conical pad racks, a double-head screw and a locking turntable; the cone expanding rings are of tubular bodies, a plurality of axial strip grooves are uniformly distributed on the tubular bodies,the cone expanding plugs are of frustums, the centers of the frustums are provided with opposite threaded holes, the locking turntable is jointed to the opposite end faces of two tubular piles through a plurality of balls placed on circumferential arc grooves of two sides before the two tubular piles are butted, the two cone expanding plugs are twisted on the double-head screw in the center of the locking turntable, the internal circles of fan-shaped conical blocks are sleeved on the external circles of the cone expanding plugs, a central hole of a bracket disc is sleeved on the middle part of a stud bolt, the internal circles of the cone expanding rings are sleeved on the external circles of the fan-shaped conical blocks, and the external circles of the two cone expanding rings are sleeved in the step conical holes of the front and rear tubular piles; and cone expanding butt joint is implemented by rotating the locking turntable. The quick joint is butted quickly and firmly, and improves the work efficiency.