Abstract: With the improvement of industry technology, the development and manufacture cost of agricultural machinery oil-supply system parts have been reduced. It is a new requirement to improve the overall performance of agricultural machinery. Combined with the high quality requirement of the casting of oil supply system, it is necessary to check the pressure leakage, and it is very difficult to guarantee the size and internal quality at the same time, and it is very difficult to make the casting quickly in short term, select the appropriate rapid manufacturing process route. The main processes, such as casting structure optimization design, casting process design, casting process simulation optimization, 3D printing 3DP sand mold, electromagnetic vacuum pressure casting, quality inspection, etc., to realize the development of oil supply system components. This production process solves the problems of quality, cycle and cost in the process of oil supply system development. The application of this technology in the metal products industry has a great economic and social price.