A spherical-form measuring apparatus (1, 201, 301) for measuring a sphere (20, 120) that includes a sphere part (22, 122) and a stem part (24, 124) having a central line passing through the center of the sphere part, the apparatus comprising: a sphere (20,120) including a stem part (24,124) and a sphere part; a table; a holding unit (10, 210, 310) placed on the table, for holding the sphere (20, 120) to be measured; and a probe for measuring the contour form of the sphere part (22, 122) in a plane parallel to the table, wherein the holding unit (10, 210, 310) includes: a base part (12, 212, 312) which is placed on the table; and a vertical holding part (14, 214, 314) and an inclined holding part (16, 216, 316) which are placed at separate positions on the base part (12, 212, 312); wherein the vertical holding part (14, 214, 314) is configured to hold the end of the stem part (24, 124) with the stem part (24, 124) set in a direction perpendicular to the surface of the table such that the sphere part (22, 122) is positioned at a given position; wherein the inclined holding part (16, 216, 316) is configured to hold the end of the stem part (24, 124) with the stem part (24, 124) set in a direction at an angle with respect to the surface of the table such that the sphere part (22, 122) is positioned at the given position; and wherein the vertical holding part (14, 214, 314) and the inclined holding part (16, 216, 316) are disposed such that a center axis of the vertical holding part (14, 214, 314) in the direction perpendicular to the surface of the table and a center axis of the inclined holding part (16, 216, 316) in the direction set at the angle with respect to the surface of the table form a single intersection point at the given position and such that the distance from the intersection point to the vertical holding part (14, 214, 314) agrees with the distance from the intersection point to the inclined holding part (16, 216, 316) and further such that the center of the sphere part (22, 122) is positioned on the intersection point when the end of the stem part is being held by said vertical holding part or by said inclined holding part. a sphere (20,120) including a stem part (24,124) and a sphere part; a table; a holding unit (10, 210, 310) placed on the table, for holding the sphere (20, 120) to be measured; and a probe for measuring the contour form of the sphere part (22, 122) in a plane parallel to the table, wherein the holding unit (10, 210, 310) includes: a base part (12, 212, 312) which is placed on the table; and a vertical holding part (14, 214, 314) and an inclined holding part (16, 216, 316) which are placed at separate positions on the base part (12, 212, 312); wherein the vertical holding part (14, 214, 314) is configured to hold the end of the stem part (24, 124) with the stem part (24, 124) set in a direction perpendicular to the surface of the table such that the sphere part (22, 122) is positioned at a given position; wherein the inclined holding part (16, 216, 316) is configured to hold the end of the stem part (24, 124) with the stem part (24, 124) set in a direction at an angle with respect to the surface of the table such that the sphere part (22, 122) is positioned at the given position; and wherein the vertical holding part (14, 214, 314) and the inclined holding part (16, 216, 316) are disposed such that a center axis of the vertical holding part (14, 214, 314) in the direction perpendicular to the surface of the table and a center axis of the inclined holding part (16, 216, 316) in the direction set at the angle with respect to the surface of the table form a single intersection point at the given position and such that the distance from the intersection point to the vertical holding part (14, 214, 314) agrees with the distance from the intersection point to the inclined holding part (16, 216, 316) and further such that the center of the sphere part (22, 122) is positioned on the intersection point when the end of the stem part is being held by said vertical holding part or by said inclined holding part. a base part (12, 212, 312) which is placed on the table; and a vertical holding part (14, 214, 314) and an inclined holding part (16, 216, 316) which are placed at separate positions on the base part (12, 212, 312); wherein the vertical holding part (14, 214, 314) is configured to hold the end of the stem part (24, 124) with the stem part (24, 124) set in a direction perpendicular to the surface of the table such that the sphere part (22, 122) is positioned at a given position; wherein the inclined holding part (16, 216, 316) is configured to hold the end of the stem part (24, 124) with the stem part (24, 124) set in a direction at an angle with respect to the surface of the table such that the sphere part (22, 122) is positioned at the given position; and wherein the vertical holding part (14, 214, 314) and the inclined holding part (16, 216, 316) are disposed such that a center axis of the vertical holding part (14, 214, 314) in the direction perpendicular to the surface of the table and a center axis of the inclined holding part (16, 216, 316) in the direction set at the angle with respect to the surface of the table form a single intersection point at the given position and such that the distance from the intersection point to the vertical holding part (14, 214, 314) agrees with the distance from the intersection point to the inclined holding part (16, 216, 316) and further such that the center of the sphere part (22, 122) is positioned on the intersection point when the end of the stem part is being held by said vertical holding part or by said inclined holding part.