An image forming apparatus includes an image forming portion, a reversing portion configured to reverse the sheet received through a first feeding passage by feeding the sheet in a first direction and then in a second direction opposite to the first direction, a sheet feeding portion provided in a second feeding passage branching from the first feeding passage on a side upstream of the reversing portion with respect to the first direction, a first guiding surface forming the second feeding passage for guiding a first surface of the sheet fed by the feeding portion, and a second guiding surface for guiding a second surface, opposite from the first surface, of the sheet fed from the reversing portion in the second direction. The second guiding surface is movable with movement of the first guiding surface for opening the second feeding passage.