The invention provides a punching device for a strip-shaped material strip. Through the punching device, it can be guaranteed that a punching arm of a punching machine and a stepping motor of a feeding clamping mechanism are synchronous in frequency. The punching device comprises the punching arm and a punching die set connected with the lower portion of the punching arm. The die set is provided with a die pressing area. The die pressing area is connected with a feeding device in the feeding direction. The feeding device comprises a feeding track and feeding clamping mechanisms. The feeding clamping mechanisms are arranged on the two sides of the feeding track and driven through the stepping motor. The punching arm is fixedly connected with a synchronous drive arm. The stepping motor is provided with a rocker type switch. The rocker suspension end of the rocker type switch is located in the stroke of the synchronous drive arm. According to the punching device, it can be guaranteed that the punching arm and the stepping motor of the feeding clamping mechanisms are synchronous in frequency, accordingly the error of the feeding distance in the punching process is reduced, the precision of the feeding distance is guaranteed, and material waste is avoided.