Obesity is one of the main risk factors for gastroesophageal reflux disease (GERD). With the development of social economy, the global obesity population shows a continuous growth trend, leading to an increase in the incidence rate of GERD. Obesity, especially the central obesity, is closely related to GERD. The increase of intra-abdominal pressure caused by obesity may lead to the destruction of "anti-reflux barrier" through a variety of mechanical mechanisms, and the various cytokines produced by visceral adipose tissue in obesity population may contribute to the occurr-ence and development of GERD through various biological effects. The authors explore the mechanism of obesity in the occurrence and development of GERD from both mechanical and biological effects, aiming to help clinical physicians improve their understanding of GERD.