Background and Aim: Gastroesophageal reflux disease (GERD) and functional dyspepsia (FD) frequently overlap. However, no accepted treatment has yet been established for such patients. This study was conducted to identify an adequate initial treatment for patients with GERD accompanied by the postprandial distress syndrome type of FD (FD-PDS). Methods: Of the 150 patients newly diagnosed with GERD who visited our clinic, 53 patients with the typical symptoms of both GERD and FD-PDS were assessed using the modified frequency scale for the symptoms of GERD and the gastroesophageal reflux and dyspepsia therapeutic efficacy and satisfaction test questionnaires. Of those, 42 patients who completed 4 weeks of treatment were analyzed. We compared the treatment responses between the 21 patients who received proton pump inhibitor (PPI) monotherapy and 21 patients who received a PPI in combination with the prokinetic drug acotiamide. Results: Assessment of the two questionnaires revealed a marked improvement of both GERD and FD symptom scores after 4 weeks of treatment in both groups. However, there were no significant differences in any GERD or FD symptom scores at baseline, after 4 weeks of treatment and in the symptom score change between the two different treatment groups. Conclusion: The results of this retrospective study suggest no benefit of PPI-prokinetic combination versus PPI monotherapy in adult patients with FD-GERD overlap; therefore, PPI monotherapy could be an adequate initial treatment for such patients.