The invention provides a vulcanization belt chamfering core bar device. The vulcanization belt chamfering core bar device comprises a core bar body and a molding hoop body; the core bar body comprises a first core bar and an installation core bar, and the installation core bar is arranged at one end of the first core bar; and an installation hole is formed in the molding hoop body, and the installation core bar is arranged in the installation hole. The vulcanization belt chamfering core bar device further comprises a clamping hoop, a sleeve hole is formed in the clamping hoop, and the molding hoop body is arranged in the sleeve hole; and a first annular boss is arranged on the molding hoop body, a second annular boss is arranged on the left side of the first annular boss, and a shaft shoulder is arranged on the right side of the first annular boss. By means of the vulcanization belt chamfering core bar device, a rubber tube with chamfers can be formed after rubber tube vulcanization, the step of conducting chamfering with a chamfering device in the later period is omitted, the number of operation persons is decreased, and the production cost of products is reduced; and meanwhile, molding and chamfering of the products can be completed only through several working procedures, and therefore the machining cost is reduced; and by means of a rubber tube produced through the device, the chamfering consistency of the products can be guaranteed, the rejection rate is reduced, and the production efficiency is greatly improved.