The association of treatment adherence with quality of life (QOL) and the role of sickle cell disease complications were explored in children with sickle cell disease. Primary caregivers of 43 children, ages 5 years and older, and 21 children, ages 8 years and older, completed a standardized measure of QOL during an admission for pain or fever to the hematology acute care unit. Adherence was measured through medical staff ratings, caregiver-report of sickle cell disease-related care activities, and matching of medical staff standard recommendations for treatment of pain and fever with sickle cell disease-related care activities. Sickle cell disease complications were assessed via medical file review. Pearson correlation coefficients indicated that better adherence was associated with poorer overall QOL. In follow-up analyses, although sickle cell disease complications were associated with adherence, it did not explain the negative correlation of adherence with QOL. Higher treatment adherence may interfere with activities that contribute to QOL for some children. Further research to investigate the role of sickle cell disease complications, as well as psychosocial factors, in determining both treatment adherence and QOL is suggested.