A wafer supporting mechanism including: a wafer supporting table; and a movable part supported by the wafer supporting table, wherein the wafer supporting table includes a wafer supporting portion for transfer that stands up from a first surface opposing a back surface of a wafer to be placed and is provided further toward an inner side than an outer peripheral edge of the wafer to be placed, and the movable part includes a wafer supporting portion for film formation that is positioned further toward an outer peripheral side of the wafer to be placed than the wafer supporting portion for transfer and is relatively movable with respect to the wafer supporting table in a standing direction of the wafer supporting portion for transfer.