The way in which disinfectants effect sterilization can be summarized into the following aspects: restrict the active transport of membrane; hinder the metabolism of microorganisms; disturb the DNA duplication of microorganisms; and break the microbial cells in a bid to bring about the leakage of intracellular constituents and condensation of intracellular constituents. Disinfectant plays an important role in controlling and killing bacteria, but the bacteria can also acquire resistance to disinfectants. The mechanisms of bacterial disinfectant-resistance can be active through formation of biofilm, prevention or efflux system to reduce penetrating disinfectant molecules, inactivation of the disinfectant, and some other disinfectant resistance phenotype and so on. Among these mechanisms, the biofilm has a great importance because it can prevent the disinfectant molecules from penetrating into the bacterial cells or inactivate the disinfectants before they have penetrated into the cells. It is suggested that studies centered on the resistance mechanism of major actually-contaminated bacteria have great value and practical significance in controlling the contamination of bacteria in the future.