A foot arch support device includes a base seat, a movable unit, high and low heel members, and an actuating unit. The base seat includes a first base plate. The movable unit includes a movable plate that is movable relative to the first base plate between high and low curvature positions. When the low heel member is coupled to the base seat, the movable plate is at the low curvature position. When the high heel member is coupled to the base seat, a support part of the high heel member abuts against the movable plate, and the movable plate is pushed by the high heel member to the high curvature position. The actuating unit is operable for permitting removal of a selected one of the high and low heel members from the base seat.