A cutting tool for cutting a rotationally symmetrical surface of a rotating workpiece, the cutting including the step of feeding the cutting tool in a direction inclined with respect to a rotational axis of the rotationally symmetrical surface while holding the cutting tool in contact with the rotationally symmetrical surface, in the step of feeding the cutting tool, the cutting tool having a point being in contact with the rotationally symmetrical surface, the point shifting as the cutting tool is fed, the cutting tool comprising: a rake face; a flank face; and a cutting edge connecting the rake face and the flank face, the cutting edge as seen from above the flank face having a shape including at least one arc, the arc having a radius of curvature of not less than 100 mm and not more than 500 mm, characterized in that the cutting edge as seen from above the flank face further includes: a first end having a convex shape, the first end corresponding to an end which contacts to the rotationally symmetrical surface at a start of cutting the rotating workpiece; and a second end opposite the first end and having a convex shape, the second end corresponding to an end which contacts to the rotationally symmetrical surface at an end of cutting the rotating workpiece, and the first end and the second end each having a radius of curvature smaller than the radius of curvature of the arc, and the flank face, as seen from above the flank face, having a shape tapering from the first and second ends toward a back surface opposite to the rake face. in the step of feeding the cutting tool, the cutting tool having a point being in contact with the rotationally symmetrical surface, the point shifting as the cutting tool is fed, the cutting tool comprising: a rake face; a flank face; and a cutting edge connecting the rake face and the flank face, a rake face; a flank face; and a cutting edge connecting the rake face and the flank face, the cutting edge as seen from above the flank face having a shape including at least one arc, the arc having a radius of curvature of not less than 100 mm and not more than 500 mm, characterized in that the cutting edge as seen from above the flank face further includes: a first end having a convex shape, the first end corresponding to an end which contacts to the rotationally symmetrical surface at a start of cutting the rotating workpiece; and a second end opposite the first end and having a convex shape, the second end corresponding to an end which contacts to the rotationally symmetrical surface at an end of cutting the rotating workpiece, and a first end having a convex shape, the first end corresponding to an end which contacts to the rotationally symmetrical surface at a start of cutting the rotating workpiece; and a second end opposite the first end and having a convex shape, the second end corresponding to an end which contacts to the rotationally symmetrical surface at an end of cutting the rotating workpiece, and the first end and the second end each having a radius of curvature smaller than the radius of curvature of the arc, and the flank face, as seen from above the flank face, having a shape tapering from the first and second ends toward a back surface opposite to the rake face.