Objective:To clone the cDNA in full-length of human mammaglobin,do prokaryotic expression and purify hMAM protein,as a basis for early diagnosis of breast cancer.Methods :hMAM cDNA was amplified through RT-PCR from breast cancer tissue and breast cancer cell line MD-MB453,and the recombination pQE40-hMAM vector was constructed and expressed in E.Coli.M15 after induction by IPTG.The fusion protein was purified with Ni-NTA-His affinity chromatography. Results: Two subtypes of hMAM cDNA and the hMAM(Isoform) cDNA were found,in which consisted of 270 bp,different from the wildtype hMAM cDNA of 279 bp on nine continuous base pair missing.The fusion protein formed inclusion body in prokaryotic expression system and the renatured protein was purified which purity was about 97%.Conclusion: The recombinant hMAM was successfully purified.