Microbiologically Influenced Corrosion behavior of copper manganese aluminum alloy (CMA) were studied in the environment of sulfate-reducing bacteria (SRB). Surface topography of microorganism films were observed by using atomic force microscopy (AFM) and Scanning Electron Microscope (SEM), The result showed that number of SRB were a little, so that microorganism films can’t form in the surface of CAM; Microscopic structure was analyzed in the process corrosion, with increase of exposure time, selective corrosion occurred mainly on containing Al at a high level of β-phase and κ-phase. X-ray Photoelectron Spectroscopy (XPS) showed the main component of corrosion product was Sulphide. The change of Ecorr and corrosion current density in culture medium containing SRB was greater than it in 3.5% NaCl. It showed that the selective corrosion of the copper was accelerated by the metabolism substance. The content of sulfide was increasing with exposure time increasing.