A quick-release and quick-installation hinge assembly includes a hinge to which a toilet lid is rotatably connected, a key plate fixed on a toilet bowl, and a limiting member. The hinge is fixedly provided with a hinge base fitted with the key plate. The hinge base and the key plate are in insertion fit in a lateral direction. The limiting member is provided with an inserting portion. The key plate is provided with an inserting hole that is in insertion fit with the inserting portion for position limitation. The inserting portion is fitted with the inserting hole for position limitation to prevent the hinge base and the key plate from being separated from each other in the lateral direction. The inserting portion penetrates through the inserting hole. The quick-release and quick-installation hinge assembly realizes a stable convenient connection structure between the hinge base of the hinge and the key plate.