The invention belongs to the technical field of nuclear power maintenance, and relates to a reliability verification device for the loading and unloading machine gripping apparatus of a pressurized water reactor nuclear power station. The reliability verification device comprises an upper supporting plate, a plurality of pull rods, a connector, a gripping apparatus verification platform and a driving device; the driving device can drive a clamping sleeve to move up and down through driving the upper supporting plate to move up and down together with the pull rods, so that the loading and unloading machine gripping apparatus can be controlled to be locked or unlocked; and the driving device can also drive a control sleeve to move up and down through driving the connector to move up and down, so that the the opening and closing of the gripper of the loading and unloading machine gripping apparatus can be controlled. With the reliability verification device of the embodiments of the invention adopted, the detection and run-in test of the locking function of the loading and unloading machine gripping apparatus and the opening and closing function of the gripper of the loading and unloading machine gripping apparatus can be performed under a no-load test state; and maintainers can be facilitated to contact the surfaces of parts which are still scratched under a no-load test state.