Quality of life (QOL) after hematopoietic cell transplantation (HCT) is compromised by chronic GVHD. In a prospectively assembled multicenter cohort of adults with chronic GVHD (n = 298), we examined the relationship between chronic GVHD severity defined by National Institutes of Health (NIH) criteria and QOL as measured by the SF-36 and FACT-BMT instruments at time of enrollment. Chronic GVHD severity was independently associated with QOL, adjusting for age. Compared with population normative data, SF-36 scores were more than a SD (10 points) lower on average for the summary physical component score (PCS) and role-physical subscale, and significantly lower (with magnitude 4-10 points) for several other subscales. Patients with moderate and severe cGVHD had PCS scores comparable with scores reported for systemic sclerosis, systemic lupus erythematosus, and multiple sclerosis, and greater impairment compared with common chronic conditions including diabetes, hypertension, and chronic lung disease. Moderate to severe cGVHD as defined by NIH criteria is associated with significant compromise in multiple QOL domains, with PCS scores in the range of other systemic autoimmune diseases. Compromised QOL provides a functional assessment of the effects of chronic GVHD, and may be measured in cGVHD clinical studies using either the SF-36 or the FACT-BMT.