There is provided a ventilation structure formed in an automobile door, which is made up of a door inner panel having a hole therethrough. A door hole seal is installed in an interior side of the door inner panel. The door hole seal has a slit or an air hole nearby the hole of the door inner panel, and it covers at least the hole. A door trim is installed on the interior side of the door inner panel sandwiching the door hole seal in combination with the door inner panel. There is/are partially or successively formed a gap or gaps between a periphery of the door trim and the door inner panel. At the time the door is closed, the air in the interior of an automobile is ejected to the exterior of the automobile through the gap or the gaps, the slit or the air hole, and a drain hole which is formed in the door inner panel.