An air discharge device is configured to discharge an air flow. The air discharge device includes a main hole for discharging an air flow as a working air flow, an auxiliary hole provided around the main hole to discharge a support air flow, and a vortex suppression structure configured to suppress development of vortices generated in a velocity boundary layer of the working air flow at a downstream side of an outlet of the main hole. This vortex suppression structure is configured to make a central portion of the thickness of the velocity boundary layer of the working air flow at the downstream side of the outlet of the main hole to be closer to a mainstream of the support air flow, at the downstream side of the outlet of the main hole.