Objective To study the effect of mannose receptor(MR) from human spermatozoa on spermegg fusion. Methods The Balb/c mouse was immunized with the purified mannose receptor(pMR) which was isolated from motile human sperm by mannoseagarose gel affinity chromatography and the antiMR serum was harvested. Human sperm after induction of acrosome reaction was pretreated with antiMR serum and subsequently processed in sperm penetration assay (SPA). Results The antiMR serum can inhibit human spermatozoa from binding and penetrating zonafree golden hamster eggs with a dosedependent reduction of Fertilization rate(FR) and Penetration index(PI).Conclusion