OBJECTIVES: Morbidity from GI symptoms in diabetes is considered to be high, but no studies have quantified the impact of GI symptoms in diabetes on health-related quality of life. We hypothesized that diabetics reporting increased GI symptoms would experience more impaired quality of life. METHODS: Subjects from the community with diabetes (n = 892) and outpatients with diabetes (n = 209) were recruited for this study. Subjects were divided into type 1 (diabetes diagnosed at age <30 yr and requiring insulin) and type 2. A validated questionnaire measuring GI symptoms and diabetes status and the Short Form-36 were completed. The results were compared with Australian normal data. GI symptom groups measured were frequent abdominal pain, bowel-related abdominal pain, reflux, dyspepsia, constipation, diarrhea, and fecal incontinence. RESULTS: There was a clinically significant decrease in quality-of-life scores in diabetics compared with population norms across all subscales. The impact on quality of life in diabetes was predominantly observed in type 2 diabetics. The quality-of-life scores in all subscales decreased markedly with increasing numbers of distinct GI symptom groups, and this was similar in community and outpatient diabetics. For all the Short Form-36 subscales, GI symptom groups were significantly (all p < 0.0001) associated with poorer quality of life in diabetes, independent of age, gender, smoking, alcohol use, and type of diabetes. CONCLUSION: GI symptoms impact negatively on health-related quality of life in diabetes mellitus.