The working principle of the mold for bottle embryo of snack can is to send powdered or granular plastic from the hopper of injection molding machine into a heated barrel; After heating, melting and plasticizing, with the help of the thrust of plunger or screw, the material is compressed and moved forward, and injected into the closed cavity with lower temperature at a faster speed through the nozzle at the front end of the barrel; After a certain period of cooling and solidification, the mold is opened to obtain the product.