Abstract: A protective pad to be secured within the thumb hole of a bowling ball on the side opposite from that gripped tightly by the thumb, comprising a resilient synthetic resin foam member having a right parallelepiped configuration except for one tapered edge, and a relatively friction-free synethetic resin tape having a pressure sensitive adhesive on an entire surface thereof to which a major face of the foam member is secured, the tape having dimensions greater than the foam member on not more than three sides thereof. The foam member is placed within a thumb hole with the tapered edge spaced inwardly from the entrance to the hole, and the tape is secured to the wall of the thumb hole on the sides overlying the foam member.