BACKGROUND/AIMS: Belching is the act of expelling gas from the stomach or esophagus noisily through the oral cavity. Although it is a physiological phenomenon, belching may also be a symptom of upper gastrointestinal diseases such as reflux esophagitis and functional dyspepsia (FD). A detailed epidemiology of belching has not yet been reported. The aim of this study is to examine the prevalence and clinical characteristics of clinically significant belching (CSB) in adults. METHODS: We analyzed 1998 subjects who visited the hospital for annual health checkups. Belching was evaluated by a simple question "Do you burp a lot?" and scored as 0 (never), 1 (occasionally), 2 (sometimes), 3 (often), or 4 (always). Subjects with CSB were defined as having scores ≥ 3. We also collected the clinical parameters, endoscopic findings, and data according to the Athens Insomnia Scale, Rome IV questionnaire, and Hospital Anxiety and Depression Scale (HADS). RESULTS: Of the 1998 subjects, 121 (6.1%) had CSB. Subjects with CSB had FD more commonly than reflux esophagitis, but presence of heartburn was high (10.7% vs 3.1%). In addition, the HADS and Athens Insomnia Scale scores in subjects with CSB were significantly higher than those in subjects without CSB. Presence of heartburn (OR, 2.07; 95% CI, 1.05-4.09), presence of FD (OR, 2.12; 95% CI, 1.33-3.36), anxiety/depression (OR, 2.29; 95% CI 1.51-3.45), and sleep disturbances (OR, 1.73; 95% CI, 1.14-2.61) were significantly associated with CSB. CONCLUSION: The detailed epidemiology of belching in the general adult population was clarified.