Abstract: Newborn larva (NBL) antigens of Trichinella spiralis were analysed by Immuroblot,and were comparied with the adult and muscle larva antigens.The SDS-PAGE patterns of NBL somatic constituents consisted of about 40 polypeptide bands,which were obviously different from those of adult and muscle larva.Immunoblot analysis indicated that immunization with NBL could induce a stage specific immune response.The molecular weight of specific NBL antigens were 129,120,89,87,79,74,72,64,58,43,40,38,34,32,and 20kDa.But during the natural course of the infection,we could not detect the antibodies of anti-NBL in the host.