PURPOSE: To obtain high quality glass such as crystal glass with superior heat insulating effect and small heat consumption per unit quantity of product glass by melting raw materials of glass in a glass melting furnace provided with a small charging port of the raw materials and a closable damper and constructing the upper part of the furnace to have a specified wall structure.

CONSTITUTION: A full electric glass melting furnace is constructed to a structure comprising a raw material charging port 5 which is made to small size so small as almost the same size as a charging basket 3 and a damper 6 for preventing heat radiation before the charging port 5, constructing on one hand, an upper wall 4 of the melting furnace to layers of for example, A-Z-S type electrocasted brick 11 in 15W20cm thickness, high alumina brick 12 in 6W10cm thickness, and heat insulating fire brick 13 in 10W15cm thickness from the inside surface toward the external wall, thus giving high resistance to high temp. and high heat retaining and insulating property to the structure. The glass raw material 1 are charged to a basket 3 at the top 4 of the charging device 2 of the raw material. Then, the damper 6 is closed to melt the raw material for the glass successively from the lower part of the raw material layer 7 and the melt is allowed to pass the highest temp. part 9 in the form of glass and generated foams in the glass are sufficiently removed. Thus, high quality glass is obtd. from the outlet 8 of the melting furnace.