Non-erosive gastroesophageal reflux disease (NERD) refers to a disease that has typical gastroesophageal reflux symptoms but lacks endoscopic esophageal mucosal damage. Its exact pathogenesis remains unclear. Studies have shown that the occurrence and development of NERD may be related to the gastrointestinal flora. The digestive tract flora can directly or indirectly participate in the occurrence and development of NERD by affecting the body’s immune, metabolic, neurological and other functions. In order to further clarify the possible correlation between NERD and gastrointestinal flora, this article reviews the research progress on the correlation between NERD and gastrointestinal flora, with a view to providing new ideas for the diagnosis and treatment of NERD.