A sheet processing apparatus includes a support unit on which sheets are stacked together as a sheet stack, first and second binding units that respectively perform first and second binding processes to bind the sheet stack as first and second sheet stacks, a transporting unit that transports the first and second sheet stacks toward first and second paths, respectively, which are in opposite directions, a reversing-and-transporting unit disposed at the second path to transport the second sheet stack such that upper and lower sides thereof are reversed, a first transported-sheet-stack support unit that is disposed at the first path and on which the first sheet stack transported by the transporting unit is placed, and a second transported-sheet-stack support unit that is disposed at the second path and on which the second sheet stack reversed and transported by the reversing-and-transporting unit is placed.