Water pressure testing device

The invention relates to a water pressure testing device. The water pressure testing device comprises a support and is characterized in that a workpiece fixing seat is mounted at one end of the support, a limiting cushion plate used for holding a workpiece is arranged on the inner side of the workpiece fixing seat, the inner end face of the workpiece fixing seat contacts with one end face of the workpiece, and a water inlet pipe is connected to the outer end face of the workpiece fixing seat; a movable seat is slidably arranged at the other end of the support and is connected with a power outlet end of a driving device; a pressing block is mounted on the movable seat, and one side, facing towards the workpiece fixing seat, of the pressing block serves as a sealing face in close fit with the workpiece; a limiting stop block matched with the limiting cushion block is arranged below the pressing block. The workpiece fixing seat and the movable seat are horizontally arranged on the two sides of the workpiece respectively. Sliding rails are arranged on the support, and sliders fixed to the movable seat are arranged on the sliding rails. The water pressure testing device has the advantages that sealing of a mold cavity of the workpiece during water pressure testing can be guaranteed, pressure influence on the workpiece from the testing device is reduced, and accuracy of a testing result is guaranteed.