In a method of manufacturing a glass molding, a lower mold includes a recess having a bottom portion and a side portion surrounding the bottom portion, and an outer peripheral planar portion surrounding an upper end of the side portion. A crossing angle between the side portion and the outer peripheral planar portion is set at more than or equal to 45 degrees. A dropping volume of the molten glass drop is such that, when dropped onto the lower mold, a volume of the molten glass drop located above the outer peripheral planar portion is 1.5 times to 6.0 times the volume of the molten glass drop filling the recess.