Background/aims: Dyspepsia and gastroesophageal reflux disease are common chronic diseases. In the clinical setting, some patients express both problems together; however, little is known about the real prevalence of the presence of the two symptoms. Turkey is particularly interesting because of differences observed from developed countries. We aimed to derive data from our previous prevalence of gastroesophageal reflux disease study and evaluate the overlap of the two symptoms. Methods: We used a previously validated and culturally adapted reflux questionnaire, which was translated into Turkish. The questionnaire was applied to 630 randomly selected subjects older than 20 years living in a population of 8857 adults. Results: 28.6% (180 / 630) of all responders defined dyspepsia within the last 12-month period. When symptom prevalence was considered at least weekly, the prevalence was 10% for heartburn, 15.6% for acid regurgitation, and 20% for either symptom. While the prevalence of gastroesophageal reflux disease was 29.4% in patients with dyspepsia, dyspepsia was found in 43. 1% of patients with gastroesophageal reflux disease. Only 21% of symptomatic subjects or 8.4% of the entire study population had both symptoms. Dyspepsia was defined as the most bothersome symptom. 54.3% of all dyspeptic patients and 67.3% with both gastroesophageal reflux disease and dyspepsia used a gastric medication (p>0.05). 29.9% of subjects with dyspeptic symptoms defined antacid consumption and 28.3% acid inhibitor therapy. Conclusion: Dyspepsia was defined as the most bothersome symptom compared to gastroesophageal reflux disease symptoms. The prevalence of dyspepsia in patients with gastroesophageal reflux disease is more common than vice versa. However, the overlap of the two symptom groups was lower than expected in this low-income, Caucasian population.