To provide an indoor unit of an air conditioner, in which a horizontal blade is easy to take a desired attitude.

This indoor unit 10 of the air conditioner includes a vertical wind direction adjustment blade 30, first pushing-out mechanisms 41, 51, 61 moving the first connecting sections 31, 32, 33 of the vertical wind direction adjustment blade 30, second pushing-out mechanisms 71a, 71b moving the second connecting sections 34, 35 of the vertical wind direction adjustment blade 30, and a control unit 84 for changing the attitude of the vertical wind direction adjustment blade 30 by moving the first connecting sections 31, 32, 33 and the second connecting sections 34, 35 to prescribed positions by controlling the first pushing-out mechanisms 41, 51, 61 and the second pushing-out mechanisms 71a, 71b. The control unit 84 controls driving of the second pushing-out mechanisms 71a, 71b so that the second connecting sections 34, 35 are moved to the prescribed positions after moved to an original position, when the positions of the first connecting sections 31, 32, 33 are moved.