The invention provides a self-powered high-voltage switch on-off performance testing device which comprises a pressure container, a moving arc contact and a static arc contact, wherein the moving arccontact and the static arc contact are arranged in the pressure container. The static arc contact is transmissibly connected with an operation mechanism. The moving arc contact is mounted in the pressure container through a contact seat. The contact seat is provided with an expansion air chamber which is provided with a nozzle and has fixed volume. The expansion air chamber is provided with a first sensor for detecting air pressure in the expansion air chamber. The self-powered high-voltage switch on-off performance testing device has beneficial effects of preventing instantaneous movement ofthe sensor, facilitating sensor arrangement, preventing transient impact, and ensuring reliability of a measuring result. The sensor records the air pressure change of the expansion air chamber. A relation between the air pressure of the air chamber and on-off performance can be obtained through the arc extinguishing characteristic, thereby supplying data support for structure optimization of theair chamber in a real product, and supplying guidance data for designing of a later-period trial manufactured batch production prototype.