PURPOSE: A square shaft golf putter is provided to allow the uniform power to be delivered from a putter head to a golf ball when a golf ball is struck. CONSTITUTION: A square shaft golf putter(100) comprises a shaft(110) which has any one shape selected from a rectangle bar and a rectangular pipe whose inside is hollow; a putter head(120) prepared in the one end of the shaft; and a grip(130) prepared in the other end of the shaft. The outer edge of the long axis of the shaft is rounded in concave or in convex or has at least two edges to have a polygonal shape. The round has a radius of 0.001~24.999 mm.
