An air conditioner (100; 200) that has a fan inside and blows out air through an air outlet, the air being sucked by the fan from an air inlet, the air outlet being defined by an upper wall surface, a lower wall surface, a left wall surface, and a right wall surface, the air conditioner comprising: a first vertical wind direction deflecting plate that is disposed in the air outlet and is rotatable; a second vertical wind direction deflecting plate that is disposed in the air outlet, is located below the first vertical wind direction deflecting plate, and is rotatable while maintaining substantially parallel to the first vertical wind direction deflecting plate; an auxiliary wind direction plate that is disposed on an upper surface of the first vertical wind direction deflecting plate, the auxiliary wind direction plate including a support piece causing the auxiliary wind direction plate to be supported by the first vertical wind direction deflecting plate with a predetermined gap with the first vertical wind direction deflecting plate; and a first longitudinal blade and a second longitudinal blade each being disposed on the auxiliary wind direction plate, wherein the auxiliary wind direction plate has a lower surface facing the first vertical wind direction deflecting plate, and an upper surface on a side opposite to the lower surface, the auxiliary wind direction plate has a first end and a second end in a left-right direction from the left wall surface toward the right wall surface, characterized in that the first longitudinal blade is erected near the first end of the upper surface of the auxiliary wind direction plate, and the second longitudinal blade is erected near the second end of the upper surface of the auxiliary wind direction plate, each of the first and second longitudinal blades has an upper portion and a lower portion, the upper portions are disposed at the first and second ends of the upper surface of the auxiliary wind direction plate, the lower portions protrude from the lower surface of auxiliary wind direction plate, and are connected to the upper surface of the first vertical wind direction deflecting plate, the first and second longitudinal blades are disposed at the first and second ends of the auxiliary wind direction plate, respectively, and the lower portions include a rotation shaft of the first vertical wind direction deflecting plate. a first vertical wind direction deflecting plate that is disposed in the air outlet and is rotatable; a second vertical wind direction deflecting plate that is disposed in the air outlet, is located below the first vertical wind direction deflecting plate, and is rotatable while maintaining substantially parallel to the first vertical wind direction deflecting plate; an auxiliary wind direction plate that is disposed on an upper surface of the first vertical wind direction deflecting plate, the auxiliary wind direction plate including a support piece causing the auxiliary wind direction plate to be supported by the first vertical wind direction deflecting plate with a predetermined gap with the first vertical wind direction deflecting plate; and a first longitudinal blade and a second longitudinal blade each being disposed on the auxiliary wind direction plate, wherein the auxiliary wind direction plate has a lower surface facing the first vertical wind direction deflecting plate, and an upper surface on a side opposite to the lower surface, the auxiliary wind direction plate has a first end and a second end in a left-right direction from the left wall surface toward the right wall surface, characterized in that the first longitudinal blade is erected near the first end of the upper surface of the auxiliary wind direction plate, and the second longitudinal blade is erected near the second end of the upper surface of the auxiliary wind direction plate, each of the first and second longitudinal blades has an upper portion and a lower portion, the upper portions are disposed at the first and second ends of the upper surface of the auxiliary wind direction plate, the lower portions protrude from the lower surface of auxiliary wind direction plate, and are connected to the upper surface of the first vertical wind direction deflecting plate, the first and second longitudinal blades are disposed at the first and second ends of the auxiliary wind direction plate, respectively, and the lower portions include a rotation shaft of the first vertical wind direction deflecting plate.