Gastroesophageal reflux disease (GERD) is a clinical condition caused by esophageal tissue damage resulting from the reflux of stomach or duodenal contents. An increasing number of GERD cases have been reported recently; however, research on this population, especially young adults, is lacking. This study aimed to investigate the dietary and lifestyle factors associated with GERD symptoms in young Korean adults. Methods: A total of 202 individuals (19–34 years old) living in Gwangju were surveyed using a questionnaire to examine their general characteristics, lifestyle, and dietary behaviors. GERD symptoms were investigated using the gastroesophageal reflux disease questionnaire (GerdQ). The participants were grouped into normal (GerdQ score ≤ 4) and caution (GerdQ score ≥ 5), and their characteristics were analyzed according to the group. Results: The findings suggested 15 participants (7.4%) belonged to the GERD caution group. More non-office workers were in the caution group than in the normal group (P < 0.05). The participants’ smoking, physical activity, sleep duration, and pillow height were not significantly different between the GERD phenotypes; however, the caution group consumed alcohol more frequently than the normal group (P < 0.001). The analyses of the participants’ eating behaviors revealed that the frequency of overeating, late-night snacking and chocolate consumption was significantly higher in the caution group (P < 0.001). Conclusion: Lifestyle and dietary behaviors were associated with GERD symptoms in young Korean adults. Further studies with larger cohorts are required to confirm these findings.