A monolithic gate driver capable of operating with a relatively small number of circuit elements is realized. A stage constituent circuit constituting each stage of a shift register includes two output terminals connected to scanning signal lines, two thin-film transistors each having a drain terminal to which an output control clock signal is supplied and a source terminal connected to the output terminal, a first-node connected to the two thin-film transistors in common, a first-node control circuit, and an input terminal for receiving a set signal. In this configuration, the first-node changes from an OFF level to an ON level based on the set signal. Further, the first-node control circuit changes the first-node from the ON level to the OFF level.