To provide a semiconductor device for which a slim border is achieved by design of a gate driver circuit.SOLUTION: A gate driver of a display device comprises a shift register unit, a de-multiplexer circuit, and n signal lines. By connecting signal lines for transmitting n clock signals, it is made possible to output (n-3) output signals per one stage of the shift register unit, and ratio of signal lines for transmitting clock signals that do not contribute to output becomes smaller in correspondence to increase in the number n, so that occupied area of the shift register unit portion is reduced, as compared with a conventional configuration where one output signal is outputted per one stage of the shift register unit, and it is made possible to achieve a slim boarder for the gate driver circuit.SELECTED DRAWING: Figure 9