A method for producing baseballs and softballs, whereby a spherical core is independently formed and then a fiber material layer is attached, this fiber material layer is evenly brushed with a layer of polyurethane (PU), and this spherical core is placed in a ball cover mold made up of two or more mold pieces, and then heated, and finally the mold is removed to reveal the complete ball. Utilizing the production tool of this invention to produce the baseballs and softballs, whereby PU is brushed onto, and penetrates into the fiber material layer on the independently formed spherical core, resulting in the ball cover forming, the ball cover and spherical core attaches and fits firmly, and the porous construction of this fiber material layer attracts air, and therefore greatly avoids bubbles forming when the outer cover is formed, which affects the quality and lifespan of the ball.