A fluid discharge device is for discharging a fluid includes a duct defining a fluid flow passage and having an opening at a downstream end of the fluid flow passage. The fluid discharge device includes a grill portion disposed in the fluid flow passage to adjust a flow direction of the fluid blown from the opening. The grill portion includes at least an adjustment fin rotatably arranged in the fluid flow passage, and is provided with an auxiliary flow passage that guides a part of the fluid flowing through the fluid flow passage to the opening as an auxiliary flow. The auxiliary flow passage is configured together with the adjustment fin to adjust a flow direction of the auxiliary flow discharged from the auxiliary flow passage to be aligned with the flow direction of the fluid flowing through the fluid flow passage.