The invention discloses a core soldering tin bar continuous casting and extruding machining system and a molding technology thereof. Metal tin is molten in a rotating ventilation purifying furnace (1), nitrogen or hexachloroethane is led through a graphite rotator (6), and slag is brought out; molten tin flows into a heat preserving furnace (2), slag and impurities are blocked through a baffle and a filter screen, and purified melt enters a discharging cavity, flows into a flow furnace (3), and finally flows into a continuous extrusion machine (4); molten metal (16) flows to an extruding groove (8a) of a rotating extruding wheel, in the rotating process of the extruding wheel, solidifying and molding of the molten metal are completed, meanwhile, cold air blows the extruding groove through a ventilation pipe (13), heat of the extruding wheel is brought away, and cooling water in a cooling water circular channel (12) cools the extruding wheel; then, the molten metal enters a mold (10) through an extruding die (9), meanwhile, scaling powder is injected into the mold, casting and extruding are carried out, and a bar (15) is obtained. The production efficiency is high, an internal structure of a product is uniform, core breaking is not prone to happening, and the surface quality is good.