The invention relates to the technical field of glass melting furnace structures, and discloses an arch structure of a glass melting furnace locking neck. The structure is characterized in that the structure comprises a plurality of sequentially bonded bricks; the bricks are wedge-shaped; and the brick on the outer side of the arch structure abuts against a tank wall of the melting furnace. The arch structure provided by the invention is wedge-shaped, and the brick on the outer side is stressed by extrusion force from the outside. Therefore, bricks in the arch structure can be firmly bonded. Even if the arch structure is in a high-temperature environment for a long time, and is corroded by sulfur and alkaline atmospheres, the bricks do not fall. The bricks are prevented from falling into glass liquid in the melting furnace, such that glass quality is not affected. The arch structure do not need to be fixed by using steel structures, such that energy consumption of the melting furnace is reduced, locking neck operation space is increased, and melting furnace stability and safety are improved.