The invention discloses a cold-chamber die casting machine which comprises a machine seat, a first mounting frame, a second mounting frame, guiding columns, sliding rails, a transverse-moving slidingplate, sliding sleeves, a squeezing cavity, a die casting air cylinder, a concave die plate, a liquid inlet pipe, a supercharging piston, a liquid inlet pipe orifice, a material filling hole, a convexdie block, an ejecting air cylinder, a positioning partition plate, an ejecting plate, a convex die main body plate, through holes, ejecting pins, sealing vales, a high-pressure air pump, a cooler and a concave surface plate. The cold-chamber die casting machine disclosed by the invention is compact in structure and convenient to use; by adoption of the structural design that an ejecting device is additionally arranged on the convex die plate, a casting can be directly ejected, the trouble that the casting needs to be directly taken by people out of a die can be avoided, the die casting efficiency can be improved, and the personal safety of an operating worker can be guaranteed; through high-pressure cooling airflow jetted from air ports of the ejecting pins, a finished workpiece can be quickly cooled, the cooling speed in a die casting process of the workpiece can be improved, and the more uniform cooling effect can be achieved; and meanwhile, waste scraps on the workpiece can be effectively removed and the quality of a finished die casting product can be improved.