A lifter including: a roller caused to abut against a cam thereby to be pressed; and a lifter body rotatably supporting the roller and housed in a guide hole of a lifter guide so as to be reciprocable in the guide hole, and wherein the lifter body includes a cylindrical part having two axial ends and a skirt formed at the one axial end side and a cylindrical body formed at the other axial end side; the lifter body further includes a rotation stopper integrally formed to protrude outward from the other axial end of the cylindrical body, the other axial end being located opposite a side where the skirt is located, the rotation stopper preventing the lifter body from being rotated about an axis thereof relative to the lifter guide; the skirt includes a pair of flat portions parallel to each other, the flat portions having respective shaft support holes through which a support shaft of the roller is coaxially inserted; the skirt has a part excluding the flat portions, the part having an outer periphery formed into an arc-shaped portion slidable on the inner periphery of the guide hole; the flat portions are disposed opposite to end surfaces of the roller so as to cover the end surfaces of the roller respectively; the arc-shaped portion is disposed opposite to an outer periphery of the roller so as to cover the outer periphery of the roller; and the cylindrical body has an outer periphery continuous with an outer periphery of the arc-shaped portion with respect to an axial direction so as to be coplanar without any step, so that the outer periphery of the cylindrical body is formed into a sliding surface which is slidable on the inner periphery of the guide hole together with the outer periphery of the arc-shaped portion. a roller caused to abut against a cam thereby to be pressed; and a lifter body rotatably supporting the roller and housed in a guide hole of a lifter guide so as to be reciprocable in the guide hole, and wherein the lifter body includes a cylindrical part having two axial ends and a skirt formed at the one axial end side and a cylindrical body formed at the other axial end side; the lifter body further includes a rotation stopper integrally formed to protrude outward from the other axial end of the cylindrical body, the other axial end being located opposite a side where the skirt is located, the rotation stopper preventing the lifter body from being rotated about an axis thereof relative to the lifter guide; the skirt includes a pair of flat portions parallel to each other, the flat portions having respective shaft support holes through which a support shaft of the roller is coaxially inserted; the skirt has a part excluding the flat portions, the part having an outer periphery formed into an arc-shaped portion slidable on the inner periphery of the guide hole; the flat portions are disposed opposite to end surfaces of the roller so as to cover the end surfaces of the roller respectively; the arc-shaped portion is disposed opposite to an outer periphery of the roller so as to cover the outer periphery of the roller; and the cylindrical body has an outer periphery continuous with an outer periphery of the arc-shaped portion with respect to an axial direction so as to be coplanar without any step, so that the outer periphery of the cylindrical body is formed into a sliding surface which is slidable on the inner periphery of the guide hole together with the outer periphery of the arc-shaped portion.