A water changing device for aquaculture breeding, comprises a breeding box. A drainage pipe is inserted into the inner wall below the breeding box; the drainage pipe has an L-shaped structure, and the horizontal side is located at the lower side of the breeding box; a sealing block is tightly inserted above the drainage pipe; a circular ring is arranged on the outer side wall of the upper end of the drainage pipe; a groove is arranged above the circular ring along the circumferential direction, and a filter screen is tightly inserted into the groove; the side wall of the drainage pipe below the breeding box is fixedly connected with a horizontal rod, and one side of the side wall below the breeding box close to the horizontal rod is fixedly provided with a threaded rod.