Abstract: A spherical structure constituting a practice golf ball and integrally formed of a tough synthetic resin has a polar axis and has: a circular equatorial vane perpendicular to the polar axis; a tubular hub disposed coaxially around the polar axis; a plurality of meridian vanes of substantially semicircular shape joined at their chordal parts to the hub part and spaced at equal angular intervals; and a middle band engirdling the spherical structure around the circumference of the equatorial vane, the semicircular outer edges of the meridian vanes and the middle band forming the outer spherical contour of the practice golf ball.