A shift register employs only a thin film transistor of the same type channel and has a level shifter built-in. A shift register with a built in level shifter includes a plurality of stages and a plurality of level shifters. The stages are connected in cascade to shift a start pulse inputted through an input terminal and sequentially output the shifted pulse. The level shifters level-shift a voltage level of the shifted pulse applied from each of the stages and outputting it.