The utility model relates to a boundary beam reinforcing screw. The connecting piece comprises a fixed connecting piece, the fixed connecting piece is right-angled, the fixed connecting piece is connected with a first screw rod, the first screw rod is connected with a second screw rod through a screw rod joint, the diameter of the first screw rod is smaller than that of the second screw rod, the second screw rod is sleeved with a sleeve, and a plurality of round holes are formed in the fixed connecting piece. The beneficial effects of the utility model are that: the utility model discloses: have: the beneficial effect is: The practical screw is simple to manufacture and convenient to use; one end of the steel wire rope is fixed on the boundary beam template; the section size of the boundary beam can be effectively controlled, the outer side screw part is detachable, cutting is not needed in the detaching process, the outer side screw part can be recycled, a screw hole cannot be reserved in the formed boundary beam, plugging is not needed, the hidden danger of water leakage of the boundary beam can be avoided, the quality is improved, operation is convenient, mastering is convenient, and partial detaching and recycling can be achieved.