To provide a device and a method for mounting a panel-like wall material excellent in mountability and effective to shorten construction period.

This panel mounting device comprises a panel lower locking member, a panel upper locking member, and a connection device connecting the upper and lower panel locking members to each other. The panel lower locking member comprises a mounting part for mounting a panel mounted on the upper side on the lower part thereof, and the panel upper locking member comprises a mounting part for mounting a panel mounted on the lower side on the upper part thereof. The connection device comprises a base part fixed to a skeleton side, a connection part for panel lower locking member, and a connection part for panel upper locking member.