Abstract: Traditional culture techniques and modern molecular techniques have showed many microorganisms are in the breast milk including Staphylococcus, Streptococcus, Enterococcus, Lactobacillus and Bifidobacterium, etc. Recent studies have demonstrated that some microorganisms in breast milk have special function such as anti-HIV, curing mastitis, getting into breast through the intestinal and so on. It was reviewed that the source, type, identification methods, special function and application of the breast milk microorganisms. This paper also provided an outlook of the research direction for microorganisms in breast milk and provided some guides for the further research and utilization of microorganisms in breast milk.