Belching may result from transient lower esophageal sphincter relaxation; therefore, it has been proposed that belching may be a manifestation of gastroesophageal reflux disease (GERD). This study was conducted to investigate the frequency of belching during esophagogastroduodenoscopy (EGD) and its association with GERD. A retrospective review was performed on prospectively collected clinical and endoscopic data from 404 subjects who underwent EGD without sedation from December 2012 to May 2013 in a training hospital in Korea. All detectable belching events during endoscopy were counted. Frequency and severity of belching events were compared between the group with and without GERD using an ordinal logistic regression model. There were 145 GERD patients (26 erosive reflux disease and 119 nonerosive reflux disease [NERD]). In the multivariable analysis, GERD was significantly associated with a higher frequency of belching events (odds ratio = 6.59, P < 0.001). Central obesity, female, and younger age were also risk factors for frequent belching during EGD. Subgroup analyses were performed in subjects without erosive reflux disease (n = 378) and NERD (n = 293). NERD was also a predictive factor for frequent belching during EGD (odds ratio = 6.61, P < 0.001), and the frequency of belching was significantly correlated with GERD severity according to the Los Angeles classification (P < 0.05). Frequent belching during EGD was associated with GERD, including NERD. Future research should focus on its adjuvant role in the diagnosis of GERD/NERD and the necessity for applying differentiated endoscopy strategies for GERD patients, leading to less discomfort during EGD in patients at risk for intolerability.