The disclosure provides a local extrusion device for high-pressing casting. The local extrusion device for high-pressure casting includes an extrusion core sleeve, an extrusion rod, an extrusion oil cylinder and an extrusion oil cylinder piston. The extrusion oil cylinder includes the extrusion oil cylinder piston, the extrusion oil cylinder piston is connected with the extrusion rod, the extrusion rod is positioned in the extrusion core sleeve, and the extrusion core sleeve and the extrusion oil cylinder are fixed.