To provide a reinforced ball for bowling, the outer cover layer of which is hardly cracked, and a manufacturing method therefor.

The reinforced ball 1 for bowling is composed of a ball base body 13, a fiber layer 12, and the outer cover layer 11, the ball base body is composed of a hard foamed polyurethane, and 5 mass% cotton yarns of 3 mm length are contained based on the ball base body. The fiber layer 12 is obtained by bonding polyester knit fabric for a work glove to the ball base body with a urethane resin adhesive. The outer coat layer is composed of a polyurethane resin. The ball base body can employ a ball for bowling, from which the outer coat layer with scratches is removed. In this manufacturing method, the ball base body is covered with the fiber layer before supported by a support rod at the center of a spherical cavity of a mold, and the polyurethane resin is injected from the inlet of the mold. Preferably, the method is applied especially to the manufacturing of a light ball for bowling.