The competition among enterprises becomes more and more drastic. In order to win the market, so as to put itself in a stead station, the enterprise put forward many advanced manufacturing modes. Virtual manufacture is put forward by American as a wholly new concept under this situation. It is thought as advanced manufacturing technology of the 21st century. Based on the analysis to the prior, the author expatiated the concept of virtual manufacture and put forward the three demands which the product model suited for the virtual manufacture must satisfy. On the bases the author set up the product model which is composed by product function express and product definition and expatiated the product function and product definition at detail.