The Inflammatory Bowel Disease Questionnaire (IBDQ) is the standard disease-specific instrument for assessment of health-related quality of life (HRQOL) in patients with inflammatory bowel diseases (IBD). A German translation has not been validated. 415 outpatient IBD-patients (Crohn's Disease n = 306, Ulcerative Colitis n = 109) completed the German version of the IBDQ (Competence network IBD, IBDQ-D), the Hospital Anxiety and Depression Scale German Version (HADS-D) and the Questions on Life Satisfaction FLZ. Face validity was assessed by a physicians' and patients' panel. Disease activity was measured by the German Inflammatory Bowel Disease Activity Index (GIBDI). With 97.3 % completed items the acceptance was high. The Cronbach's alpha for the subscales ranged from 0.88 to 0.89. The correlation coefficients with comparable subscales of other instruments ranged between 0.09 and 0.70. Patients in remission and different disease activities differed significantly (p < 0.001) in all IBDQ-D-subscales.