Abstract: In this study, superoxide dismutaes genes fesod from Magnetospirillum AMB-1 were cloned and expressed in E.coil BL21 （DE3）. The SOD gene was obtained from the genome of AMB-1 through PCR amplification, and the resulting amplified gene was cloned into an IPTG-inducible expression vector pET-20b, respectively. The expression vectors pET-20b-fesod-histag was further transformed into E.coil BL21 （DE3）. In contrast to the control BL21（DE3） / （pET-20b）, the growth curves of the recominent strains showed that the growth rates of BL21 （DE3） / （pET-20b-fesod-histag）was obviously higher than that of control. Superoxide dismutaes activity result showed that the SOD activity level of BL21（DE3）/（pET-20b-fesod-histag）per OD₆₀₀ was higher than that of control. SDS-PAGE analysis showed that fesod gene was expressed effectively and the expression product was about 22 kD. Moreover, the expression level of an hypothetical SOD protein derived from the host bacteria was gradually increasing during the IPTG inducible expression in BL21（DE3） / （pET-20b）. Molecular cloning of superoxide dismutaes genes from AMB-1 and their expression in E.coil.