Microbiologically influenced corrosion (MIC) is always a hot topic in the field of metal corrosion. Different mi-crobial species also have different effects on the corrosion of metal materials. The corrosion mechanism of single microorganism in actual environment could not fully explain the actual corrosion phenomenon due to the complexity of microorganism. In recent years, the study of mixture microorganism system has become a new research direction in the field of microbiologically influenced corrosion. The corrosion of mixture microorganism system of two microorganisms on metal surface was discussed according to the research on corrosion behavior and corrosion mechanism of single microorganism. The composition of the mixed microorganism was summarized, and the action process of the mixed system containing SRB, IOB and other typical microor-ganism was analyzed, and the effects of the interactions of different microorganisms in the mixed system on metal corrosion, such as synergism and competition, were studied. The experimental environment of current mixed microorganism system was reviewed. Several technologies were introduced to study the corrosion microstructure of mixed microorganisms on metal surface in order to show the interaction mechanism of microorganism in the mixture system more directly. Some suggestions and development directions for the study of corrosion problems in mixed microorganism system were proposed.