Aims. The association betweenHelicobacter pylori(H. pylori) infection and diarrhea-predominant irritable bowel syndrome (IBS-D) is still controversial. Here we performed a retrospective study to explore this issue.Methods. A total of 502 inpatients with Rome III confirmed IBS-D and knownH. pyloristatus from 8 hospitals were enrolled.H. pylori-positive patients, hospitalized in the recent year, were followed up to evaluate the effects ofH. pylorieradication on IBS-D clinical course.Results. Of the 502 IBS-D patients, 206 wereH. pylori-positive, with an infection rate that has no significant difference with that of the general population in Guangdong province (p=0.348). For patients followed up, no significant differences were noted as to overall symptoms (p=0.562), abdominal pain/discomfort (p=0.777), bloating (p=0.736), stool frequency (p=0.835), or stool characteristics (p=0.928) between theH. pylori-eradicated group and the control group. The results were the same in long-term follow-up patients except the improvement of bloating, which showed that the bloating score in theH. pylori-eradicated group was significantly lower (p=0.047).Conclusions. No significant correlation betweenH. pyloriinfection and IBS-D was noted. Overall, IBS-D patients may not benefit fromH. pylorieradication.