An over-the-range microwave oven includes: a housing； an electric equipment chamber which is disposed in the housing, and includes a control panel, and a drive unit； a cooking chamber which is disposed in the housing and controlled by the electric equipment chamber, and has an air inlet portion which is disposed at one side of the cooking chamber and into which outside air flows, and an opening and closing unit which is disposed at the other side of the cooking chamber and that is opened and closed based on a flow rate of flowing air； and a duct unit in the housing and disposed outside the cooking unit.
