Abstract: An abrasive water jet nozzle for strengthening, including a chamber, providing a mixing space; and a strengthening mixing assembly, providing a strengthening mixing of water with an abrasive entering the chamber, wherein the strengthening mixing assembly includes a fluid passage and a water stopper block, wherein the water stopper block is located at an eccentric position on one side of the chamber, and an outlet of the fluid passage faces the water stopper block. The provided abrasive water jet nozzle is capable of fully mixing high speed water with the abrasive particles after the high speed water entering the mixing chamber, so as to ensure the uniformity of the strengthening effect, and the formed abrasive water jet is a large circular fan-shaped jet, which can greatly improve the strengthening quality of the abrasive water jet.