Microorganisms exist as the form of community in the nature, named as biofilm. The communication and cooperation between the individuals is performed as multi-cellular behaviors, such as symbiosis, altruism, and so on. This article reviewed the cooperation behaviors and analysis, the thesis for explaining these cooperation and the ways of preventing cheating. And it introduced the concept of sociomircobiology, helping to understand the microorganism by the way of community, and to enable us to open the black box of the genetics underlying social traits.