The air discharge device includes a duct defining: a main flow path through which an air flow passes; and a main hole opened in a flat shape to discharge the air flow as a working air flow toward a downstream from the main flow path. A throttle portion is provided in the duct to reduce a flow path height of the main flow path from an upstream of the air flow toward a downstream of the air flow. A plurality of partitions are arranged to divide the main flow path in a major direction into a pair of side flow paths and at least one center flow path. The plurality of partitions are disposed in the duct such that a flow path width of the center flow path is reduced from the upstream of the air flow toward the downstream of the air flow.