Social behavior plays a pivotal role in the mental well-being of an individual. Continuous efforts in the past have led to advancements in the area of how the brain regulates emotion and cognition, while the understanding of human social behavior still remains eluded. A major breakthrough in understanding the etiology of neurological disorders is the recent insight on the role of the gut microbiota (GM). Human GM also referred to as the "forgotten organ" is home to 10(13-14) microorganisms, which is 10 times the number of cells present in the human body. In addition, the gut microbiome (total genome of GM) is 150 times greater as compared to the human genome. An emerging concept gaining worldwide focus and acceptance is that, this much big genome can potentially control human behavior and other biological functions. Herein we hypothesize on the basis of GM's ability to modify brain and behavior and that it can directly or indirectly control social behavior. This review focuses on the association of GM with various domains of social behavior like stress, cognition and anxiety.