A ventilation apparatus blows air into a vehicle compartment of a vehicle. The ventilation apparatus has a blower, a duct, a blowing outlet, guide vanes, and a turning mechanism. The blowing outlet is provided with the duct. The blowing outlet guides the air to flow along a lower surface of the duct. The guide vanes change a flow velocity component of the air in a lateral direction of the vehicle by guiding the air to flow along the guide vanes. The guide vanes are arranged in the duct on an upstream side of the blowing outlet and distanced from each other in the lateral direction. According to the above-described configuration, it is possible to provide a ventilation apparatus that can change a flow direction of air in the lateral direction of the vehicle while suppressing a pressure loss of air and a damage of the ventilation apparatus.