Abstract: China s first generation of contraceptive vaccine has been developed through the multi-center collaboration research program supported by National Research Project during the past ten years.The basic principle of the vaccine s formulation was designed to use a key pregnant-depentent,transit present,tissue specific and molecular structure well-known glycoprotein hormone—human chorionic gonadotropic hormone through the application of protein engineering techniques,the crossreactivity with three other pituitary glycoprotein hormones and the immunotolerance of the body to this "self" hormone have been overcome and the biological activity of hCG remained intact.Pre-clinical nonhuman primate toxicology & safety study has been carried out in Guangdong Primate Center successfully.Two principal investigators of this research project have received the pilot inoculation of China s first generation of contraceptive vaccine to obtain the direct experience of immune response,ten volunteers of tubular ligated female have entered into the first phase clinical pilot trial in 1995 and successfully proved that China s first generation of hCG controceptive vaccine is immunogenic,safe,no toxic reactions in human beings. The formulation of second generation of a new vaccine to enhance the immunogenecity through protein and genetic engineering is now in progress.