Use 3D printer to print the mold directly without patterns, after simulated the iron liquid components, fluid progress and solidification, we can get the below results: ①Estimate the defects when iron liquid fluiding and shrinkage, optimize pattern design and casting process. ②Reduce the working hours, stabilize and improve the quality in the foundry shop. ③Can estimate castings' microstructure and mechanical preperty.④Make the samples for several parts with the different. Make the spare parts easily. ⑤Decrease the numbers of core, Improve the accuracy by one full core.