To provide an optical component grinding tool whose grinding face diameter changes due to wear are small, as well as an optical component grinding method based on the use of this optical component grinding tool.

An optical component grinding tool 10 is equipped with a grinding unit 11, whose concave hemisphere-shaped grinding face 11a is formed on one end face of a cylindrical object, and whose external rim face 11b is in the form of a sharp edge, and a cylinder unit 12, which is made from a material softer than the optical component and designed to adhere to and cover the side face 11c of the cylindrical body of the grinding unit 11. In the method, by rotating the optical component grinding tool 10, and by causing the reciprocating movement of the optical component while the grinding-target face of the optical component is closely attached to the grinding unit 11, the grinding-target face of the optical component is ground so as to form a convex hemispherical shape.