The vacuum casting technology which uses prototype (SLA laser rapid prototyping piece, CNC products) to make silicone mold under vacuum, and is poured under vacuum conditions, such as PU, ABS, etc. Vacuum casting is also used to clone the prototype or copy the piece. It has different types including vacuum mould casting, vacuum pressure casting, vacuum sand casting and so on. This method is especially suitable for small batch production. It is a low-cost solution to solve experimental production and small batch production in a short time, and can also meet the functional test proofing of some structurally complicated engineering samples.