A shower head with an auto-locking cover includes a body unit, a rotation support seat, a seal seat and a cover unit. The seal seat is fixedly connected to an underside of the body unit. The rotation support seat is secured through the body unit and the seal seat. The rotation support seat is formed with an insertion hole and an engaging step. The cover unit is formed with a hook corresponding to the insertion hole and the engaging step. The cover unit is mounted to an underside of the rotation support seat. The rotation support seat is further formed with an elastic piece. The cover unit is formed with an engaging recess corresponding to the elastic piece. By turning the rotation support seat, the elastic piece is engaged in the engaging recess so that the cover unit is connected to the underside of the rotation support seat.