A film deposition apparatus that laminates layers of reaction product by repeating cycles of sequentially supplying process gases that mutually reacts in a vacuum atmosphere includes a turntable receiving a substrate, process gas supplying portions supplying mutually different process gases to separated areas arranged in peripheral directions, and a separation gas supplying portion separating the process gases, wherein at least one process gas supplying portion extends between peripheral and central portions of the turntable and includes a gas nozzle discharging one process gas toward the turntable and a current plate provided on an upstream side to allow the separation gas to flow onto its upper surface, wherein a gap between the current plate and the turntable is gradually decreased from a central side of the turntable to a peripheral side of the turntable, and the gap is smaller on the peripheral side by 1 mm or greater.