An apparatus for drilling holes in a glass plate has a supporting member for sucking and supporting a glass plate which is used for an automobile window or the like, as described later, and the supporting member is comprised of a suction pad for sucking the glass plate and a pair of supports for supporting the glass plate on an outer side of the suction pad. The supports are detachably mounted on the outer side of the suction pad, and the supporting member is adapted to rotate about the suction pad in an R direction. The apparatus for drilling holes in a glass plate further includes a hole forming means for forming in the glass plate holes shown in FIG. 7; a supporting means having the supporting member and for supporting the glass plate in which the holes are to be formed by the hole forming means; and a transporting means for transporting onto the supporting means the glass plate in which the holes are to be formed.