The invention discloses a push boat for lock navigation. The push boat comprises a gondola type propeller, a hull, a portside case push arm, a starboard case push arm, a bollard, a crashproof cushion block and a reinforcing rib, wherein the gondola type propeller is installed on the stern portion of the push boat, the portside case push arm on the portside is fixedly connected with the hull, the starboard case push arm on the starboard is fixedly connected with the hull, the portside case push arm and the starboard case push arm are connected together through reinforcing rib, and the bollard and the crashproof cushion block are positioned on the inner surfaces of the portside case push arm and the starboard case push arm. When a plurality of ships that has to pass the lock are loaded in the push boat, cable tying work is completed in an anchoring area, and the push boat pushes the ships to pass through the lock. In this way, a plurality of ships passing through the lock can be completed in one time, the total time of passing the lock is reduced, and the navigation efficiency is improved.