A panel gripping jig for gripping a panel, regardless of the size and shape of the panel, includes a welding unit for temporarily holding the panel. A separation unit releases the coupling state of the panel and the welding unit. A mounting arm has the welding unit mounted thereon, moves the welding unit in a longitudinal direction thereof, and has a connection part to connect the mounting arm to a working robot. A displacement unit adjusts the position of the welding unit on the mounting arm. A control board outputs control signals to operate the welding unit, the separation unit, and the displacement unit according to a user input.