Obesity has become one of the important chronic disease which threatens the human health, and gut microbiota play an important role in the occurrence and development of obesity. Proposed mechanisms for the role of gut microbiota include the increase of energy harvest from the diet, regulation synthesis and storage of fat, induction chronic low-grade inflammation, eventually leading to obesity and subsequent metabolism disorders. Elucidating the mechanism of the intestinal flora in obesity may provide new targets for the prevention and treatment of obesity.