Functional dyspepsia (FD) is a constellation of epigastric symptoms originating in the gastroduodenal region without organic and metabolic cause. However, similar confounding symptoms can also appear in patients with gallbladder (GB) dyskinesia. Therefore, symptoms of GB dyskinesia may be mistaken for FD. We aimed to identify GB dyskinesia as a cause of FD symptoms compatible with the Rome IV criteria and the need for an evaluation of GB function in patients with FD symptoms.We investigated information of patients with FD symptoms who underwent a quantitative Tc-diisoproyl iminodiacetic acid cholescintigraphy (DISIDA scan) through electronic medical records, and GB dyskinesia was judged to be the cause of the FD symptoms if the symptoms disappeared as GB function normalized on the follow-up DISIA scan in patient with decreased GB function on the initial DISIDA scan.A total of 275 patients underwent a DISIDA scan. Eighteen patients of them had FD symptoms compatible with the Rome IV criteria. Three were lost after undergoing a DISIDA scan. Eight had normal GB function, and the other 7 had decreased GB function on the initial DISIDA scan. In 4 of the 7 patients with GB dyskinesia, FD symptoms disappeared as GB function normalized. As a result, GB dyskinesia was the cause of the symptoms in 4 of 18 patients with FD symptoms compatible with the Rome IV criteria.It is necessary to evaluate GB function in patients with refractory FD symptoms because the symptoms can be caused by GB dyskinesia.