The invention belongs to the technical field of glass production, and in particular relates to a melted glass vacuumizing and defoaming device and a method thereof. The device comprises a melting furnace and an extrusion mechanism, wherein combustion chambers are formed in the periphery and bottom of the melting furnace; a combustion engine is fixedly arranged on one side of the bottom of the melting furnace; a furnace lid is arranged on the top of the melting furnace; a first connecting pipe penetrates through the furnace lid; a first vacuumizing device is connected to one side, which is far away from the furnace lid, of the first connecting pipe; the extrusion mechanism comprises a siphon; the opening end of the siphon penetrates through the side wall of the melting furnace and is arranged in the melting furnace; and a molding furnace is arranged below the opening end of the siphon. The problem that the quality of glass products is influenced by bubbles produced in the process of melting the molten glass in the melting furnace is solved.