To objectively reveal the relationship between tongue coating microbes and bitter taste, sticky and greasy taste in chronic atrophic gastritis (CAG) patients.16S rRNA high-throughput sequencing was used to detect bacterial diversity and community composition of tongue coating microbes from samples of CAG patients. LEfSe algorithm was used for discovering the different tongue coating microbes in CAG patients with or without bitter taste, also that in CAG patients with or without sticky and greasy taste.We respectively compared the features of tongue coating microbes in bitter taste, sticky and greasy taste of CAG patients. At the genus level, 25 tongue coating microbes were significantly different in CAG patients with bitter taste or without bitter taste; 17 tongue coating microbes were significantly different in CAG patients with sticky and greasy taste or without sticky and greasy taste. and were closely related to CAG patients with bitter taste. , , and were closely related to CAG patients with stick and greasy taste.and possibly contribute to bitter taste of CAG patients, and and contribute to stick and greasy taste of CAG patients, which is potential for the diagnosis and treatment of CAG.