Abstract: The present invention relates to an apparatus for blow-molding a glass bottle, and more particularly, to an apparatus for blow-molding a glass bottle in which molding air is injected into a pair of mold bodies such that molten glass accommodated in the mold bodies is formed into a glass bottle and a groove is formed at the center of the inner side of the bottom surface of the glass bottle. The apparatus for blow-molding a glass bottle of the present invention uses a blow mold (10) configured to include: a pair of mold bodies (11) forming a tubular body; a base mold (12) which molds the bottom surface of the glass bottle; and a blowing head (13) which are arranged in the upper portions of the mold bodies (11) and into which molding air is injected such that the glass bottle is expanded after primary molding and closely contacts the inner walls of the mold bodies (11) and the base mold (12).