PURPOSE: To make the heat distribution of a metallic mold itself excellent and to make the temp. control easy by constituting the metallic mold itself for the glass molding of electrically-conductive ceramic, performing the specular work on the molding surface and making the metallic mold itself such constitution that it is made hot with the electric conduction.

CONSTITUTION: The metallic molds 10 itself molding an optical glass element such as a lens are constituted of electrically-conductive ceramic and the specular work is performed on the molding surfaces 12, 14. As the electrically-conductive ceramic, SiC-ZrB2 series, SiC-Si3N4 series, SiC-B4C series and SiC-Al2O3 series ceramics are preferably used. Furthermore the electrodes 15 are respectively provided to the sides of the lengthwise direction of both an upper mold 10 and a lower mold 11 and joined to the electric power sources 16. The electrodes 15 are conducted with the electric power sources 16 and the metallic molds 10 itself are uniformly made hot and the molding is performed. Thereby the thermal strain due to the ununiformity of the heat distribution of the metallic molds 10 itself can be solved and the yield of the finished articles can be increased.