The utility model discloses a vacuum evaporation salt manufacturing heating chamber which comprises a shell, a tube box, a tube plate, a heat conduction tube bundle and a tube bundle support device, wherein the tube bundle support device is a baffling circular cage; the baffling circular cage comprises baffling rods, baffling rings and pull rods; a plurality of baffling rods are fixed on the baffling rings; the baffling rings are fixed on the pull rods in certain distance; the shell is connected to one side of the tube plate; an extended tube is connected to another side of the tube plate; flanges are fixed on the extended tube; the flanges are connected in a mode that flanges with convex-concave surfaces and necks are connected in pairs; and an uncondensed gas discharge tube and a condensed water discharge tube are mounted in a form of being tightly adhered to the tube plate. As the tube bundle support device is changed into a baffling circular cage structure, the vibration resistance of the tube bundle is improved, the shell pass flowing resistance is small, and the heat conduction efficiency is high; and as the tube plate is connected with the extended tube, the tube plate is not used as the tube plate of the flanges as well any longer, the thickness of the tube plate is reduced, gases and liquids can be thoroughly discharged, the flanges are reliably sealed, and an improved longitudinal flowing type vacuum evaporation salt manufacturing heating chamber is high in sealing capability and long in service life.