Abstract: Momordicin(Alpha-momorcharin)is a kind of multifunctional ribosome inactivating protein(RIP)with anti-tumor,anti-bacterial,anti-HIV and immunosuppressive activity.In this study,the gene encoding mature Alpha-momorcharin protein was amplified from the genomic DNA of Momordica charantia L.by using PCR(polymerase chain reaction)method.The amplified product was cloned into expression vector pET28a(+),and then expressed in the BL21(DE3)and Rosetta^TM(DE3)pLysS.Only in the Rosetta^TM(DE3)pLysS strain,the 33-kD-weight recombinant protein of Alpha-momorcharin was successfully expressed and the soluble recombinant protein was occurred when the strain was induced with IPTG at 18℃ and 22℃ temperature.The soluble recombinant protein was purified by the Ni-NTA resin and followed by Western-blotting analysis.This result revealed that the purified recombinant protein could be recognized by His-Tag antibody.It lays a foundation for further studies of the function and activity of the Alpha-momorcharin recombinant protein.