In food processing environments, various microorganisms can adhere and aggregate on the surface of equipment, resulting in the formation of multi-species biofilms. Complex interactions among microorganisms may affect the formation of multi-species biofilms and their resistance to disinfectants, which are food safety and quality concerns. This paper reviews the various interactions among microorganisms in multi-species biofilms, including competitive, cooperative and neutral interactions. Then, the preliminary mechanisms underlying the formation of multi-species biofilms are discussed in relation to factors, such as quorum sensing (QS) signal molecules, extracellular polymeric substances (EPS) and biofilm-regulated genes. Finally, the resistance mechanisms of common contaminating microorganisms to disinfectants in food processing environments are also summarized. This review is expected to facilitate a better understanding of inter-species interactions, and provide some implications for the control of multi-species biofilms in food processing.