An object of the present invention is to achieve a scanning line drive device which allows further reduction of circuit scale and production costs. A gate driver (100) of the present invention includes: a shift register circuit (1) including g latch circuits (21) to (2g); g selection circuits (8); and g level shifter circuits (3). A level shifter circuit (3) of an output drive circuit (st1) receives a pulse (61) from a NAND circuit (6) of a selection circuit (8) at its input terminal (N1); a pulse (71) from a NAND circuit (7) of the selection circuit (8) at its input terminal (N2); and a pulse (Q1) from a latch circuit (21) at its input terminal (N3). The level shifter circuit (3) of the output drive circuit (st1) outputs a voltage signal obtained by converting the voltage level of the pulse (61) from its output terminal (O1); and a voltage signal obtained by converting the voltage level of the pulse (71) from its output terminal (O2).