A discharge mechanism includes a rotary shaft, a roller member, and a deforming unit. The roller member has a peripheral surface that is coaxial with the rotary shaft, rotates together with the rotary shaft, and discharges a medium that is in contact with the peripheral surface. The deforming unit deforms the medium in such a way that a part of the medium, the part being not in contact with the peripheral surface, passes through a position that is closer to the rotary shaft than the peripheral surface is. A part of the peripheral surface, the part being in contact with the medium, is continuously displaced in an axial direction and in a rotation direction of the rotary shaft when the roller member is rotated.