BACKGROUND: Rigorous assessment of health-related quality of life (HRQL) is mandatory to establish the benefits of islet transplantation. METHODS: The 36-Item Short Form Health Survey (SF-36) and the Diabetes Quality of Life (DQOL) scales were completed by patients included in an Islet Transplantation Alone (ITA) trial (n = 10) and an Islet After Kidney (IAK) trial (n = 10). RESULTS: The two populations differed by HRQL scores at baseline, with poorer scores in ITA patients. SF-36 scores for physical limitations, bodily pain, general health perception, social functioning, and health transition improved significantly in ITA patients 6 and 12 months post transplantation. The DQOL global score was significantly improved at 6 months and remained so at 12 months, because of a significant improvement in the dimensions of satisfaction and impact of diabetes. No improvement was observed in the IAK patients. CONCLUSION: HRQL assessment may help in the selection of candidates with brittle diabetes for islet transplantation.