© 2018 The Author(s). Background: Previous studies in quality of life (QOL) in individuals with disorders/differences of sex development (DSD) have been restricted to subpopulations of the condition. We describe QOL in adult persons with DSD compared to country specific references and assess the impact of diagnosis. Methods: The multicentre cross-sectional clinical evaluation (dsd-LIFE) took place in 14 specialized clinics in six European countries. Adolescents (≥16 years) and adults having a DSD condition were included from 02/2014 to 09/2015. The main outcome QOL was measured by the WHOQOL-BREF (domains of physical health, psychological, social relationships, and environment). QOL was compared to country specific reference populations by using unpaired t-tests. Linear regression models explained the additional variance of the diagnosis on QOL. Results: Three hundred one individuals with Turner Syndrome, 219 with Klinefelter Syndrome (including XYY), 226 with 46,XX CAH and 294 with rare DSD conditions (gonadal dysgenesis, androgen insensitivity syndrome, severe hypospadias, and androgen synthesis errors or other diagnosis) took part. Compared to healthy European populations, QOL was similar in psychological, slightly worse in physical health, and slightly better in environment. In social relationships, QOL was significantly poorer compared to healthy and non-healthy reference populations. In linear regression models health status was the most important predictor of QOL; additional variance was explained by feelings about household's income in all domains, and the relationship status in social relationships. Diagnosis explained nearly no additional variance. Conclusions: Except for social relationships, most people with DSD adapt well to their life circumstances and report a good QOL. Not diagnosis, but the individual's health status is much more important than previously thought. Therefore care for people with DSD should focus more on chronic physical or mental health problems both related and unrelated to the diagnosis itself. Trial registration: German Clinical Trials Register DRKS00006072.