Objective: To explore the differences in frequency and epidemiology of functional gastrointestinal disorders (FGIDs) in a primary care setting, and to examine the health-related quality of life (HRQOL) and healthcare utilization of FGID patients based on the Rome III and Rome IV criteria. Methods: A cross-sectional study of consecutive adults in a primary healthcare setting was conducted. Differences in epidemiology, and HRQOL of common FGIDs (functional dyspepsia [FD], irritable bowel syndrome [IBS], functional diarrhea, functional constipation [FC]) between the Rome III and IV criteria were explored. Results: Among a total of 1002 subjects recruited, the frequency of common FGIDs was 20.7% and 20.9% among subjects based on the Rome III and Rome IV criteria, respectively. The frequency of IBS reduced from 4.0% (Rome III) to 0.8% (Rome IV), while that of functional diarrhea increased from 1.2% (Rome III) to 3.3% (Rome IV). In contrast, there was no significant change in the frequency of FD (7.5% [Rome III] vs 7.6% [Rome IV]) and FC (10.5% [Rome III] vs 11.7% [Rome IV]). Most of the Rome III IBS subjects (52.5%, n = 21) who did not meet Rome IV IBS criteria, fulfilled the criteria for FC, functional diarrhea, FD, or overlap syndrome. Subjects with all FGIDs, regardless of criteria, had more healthcare utilization and lower HRQOL compared to non-FGID controls. Conclusions: The Rome IV criteria alter the frequency of IBS and functional diarrhea, but not FD and FC, when compared to the Rome III criteria. Regardless of criteria, FGIDs had a significant impact on healthcare burden and HRQOL.