The utility model discloses a furnace gate device of copper solder brazing stove, it includes supporting rack (1), cylinder (17), thread bush (12) be connected with cylinder (17) piston rod, movable plate (15) be connected with thread bush (12), a left side, two chain (3) one end on the right side are connected with movable plate (15) respectively, the other end respectively with a left side, two sprocket (2) meshing backs on the right side, be connected with furnace gate (6) respectively, the guide way sliding connection of furnace gate (6) and deflector (5), install on supporting rack (1) deflector (5), install on deflector (5) top spacing link stopper (4) to be connected with supporting rack (1), install on deflector (5) unsteady bulb (7) to be located fire door (8) both sides. The utility model has the advantages of reasonable design, convenient operation, furnace gate open, close steadily, and reducible furnace gate lower extreme and fire door bottom impact prevent that the furnace body from damaging, and reducible nitrogen gas and heat run off, and be energy -concerving and environment -protective, safety.