To solve the following problem in putting faced by many people being professional and amateur golfers: a golf ball is largely deviated to the right or left from a target by inclination in putting with a conventional putter.

The sole (a ball hitting surface) of the putter is made to be a curved surface (R=250-950 mm). Lines are written at the upper center, toe side, and heel side of the putter. When putting on a hook line, the ball is hit by aligning the center of the ball to the heel side line. When putting on a slice line, the ball is hit by aligning the center of the ball to the toe-side line. Slice (right) rotation is obtained in the hook line, and hook rotation (left) is obtained in the slice line, so as to raise the establishment of cup-in. On a straight line, the ball is aligned to the upper center line, thereby allowing the player to have a sense of ease when addressing toward the cup.