A medium discharge device for discharging a medium used in an image forming apparatus, comprising: a discharge tray having a placing surface on which a medium is to be placed; a first pair of discharge rollers (22a, 23a) including a first roller rotating about a first axis extending in a predetermined direction and a second roller rotating about a second axis extending in the predetermined direction, the first roller and the second roller forming a first nip therebetween, the first pair of discharge rollers (22a, 23a) discharging the medium through the first nip onto the discharge tray; a second pair of discharge rollers (22b, 23b) including a third roller rotating about the first axis and a fourth roller rotating about the second axis, the third roller and the fourth roller forming a second nip therebetween, the second pair of discharge rollers, 23b) discharging the medium through the second nip onto the discharge tray; and a discharge guide (24, 124) for guiding the medium discharged by the first pair of discharge rollers (22a, 23a) and the second pair of discharge rollers (22b, 23b), the discharge guide (24, 124) including: a first projection (24c, 124c) disposed between the first pair of discharge rollers (22a, 23a) and the second pair of discharge rollers (22b, 23b) in the predetermined direction, the first projection (24c, 124c) projecting toward the placing surface relative to the first and second nips (51, 52) and having a first guide surface; and a second projection (24a, 124a) disposed on an opposite side of the first projection (24c, 124c) with respect to the first pair of discharge rollers (22a, 23a) in the predetermined direction, the second projection (24a, 124a) projecting toward the placing surface relative to the first and second nips (51, 52) and having a second guide surface, wherein in the predetermined direction, a length of the first guide surface is greater than a length of the second guide surface. a discharge tray having a placing surface on which a medium is to be placed; a first pair of discharge rollers (22a, 23a) including a first roller rotating about a first axis extending in a predetermined direction and a second roller rotating about a second axis extending in the predetermined direction, the first roller and the second roller forming a first nip therebetween, the first pair of discharge rollers (22a, 23a) discharging the medium through the first nip onto the discharge tray; a second pair of discharge rollers (22b, 23b) including a third roller rotating about the first axis and a fourth roller rotating about the second axis, the third roller and the fourth roller forming a second nip therebetween, the second pair of discharge rollers, 23b) discharging the medium through the second nip onto the discharge tray; and a discharge guide (24, 124) for guiding the medium discharged by the first pair of discharge rollers (22a, 23a) and the second pair of discharge rollers (22b, 23b), the discharge guide (24, 124) including: a first projection (24c, 124c) disposed between the first pair of discharge rollers (22a, 23a) and the second pair of discharge rollers (22b, 23b) in the predetermined direction, the first projection (24c, 124c) projecting toward the placing surface relative to the first and second nips (51, 52) and having a first guide surface; and a second projection (24a, 124a) disposed on an opposite side of the first projection (24c, 124c) with respect to the first pair of discharge rollers (22a, 23a) in the predetermined direction, the second projection (24a, 124a) projecting toward the placing surface relative to the first and second nips (51, 52) and having a second guide surface, a first projection (24c, 124c) disposed between the first pair of discharge rollers (22a, 23a) and the second pair of discharge rollers (22b, 23b) in the predetermined direction, the first projection (24c, 124c) projecting toward the placing surface relative to the first and second nips (51, 52) and having a first guide surface; and a second projection (24a, 124a) disposed on an opposite side of the first projection (24c, 124c) with respect to the first pair of discharge rollers (22a, 23a) in the predetermined direction, the second projection (24a, 124a) projecting toward the placing surface relative to the first and second nips (51, 52) and having a second guide surface, wherein in the predetermined direction, a length of the first guide surface is greater than a length of the second guide surface.