OBJECTIVE To investigate health-related quality of life (HRQOL) in a nationally representative sample of long-term breast cancer survivors (BCS) in Denmark. METHODS An age-stratified random sample of 2,000 female BCS > or = 5 years after primary surgery without recurrence was drawn from the Danish Breast Cancer Cooperative Group register, which is representative regarding long-term BCS in Denmark, and compared with 3,104 women of the nationally representative Danish Health and Morbidity Survey 2000. The Short Form-36 questionnaire assessed HRQOL and its association with BCS' sociodemography, type of surgery, systemic therapy, radiotherapy, time since operation, receptor status, and low/high risk protocol. RESULTS The response rate was 79%. BCS tended to rate HRQOL better than the general female population. BCS reported significantly less "bodily pain" (P < 0.0001), better "general health" (P < 0.0001), but worse "mental health" (P < 0.0001). Age interacted significantly with four other subscales (P < 0.05): Younger BCS reported worse HRQOL than equally aged women of the general population, while older BCS reported better HRQOL. Poor HRQOL was significantly associated with being single (all subscales: P < 0.05), short education (all subscales: P < 0.05, except "social function"), and high body mass index ("physical function", "role physical": P < 0.05). Breast cancer (low/high risk, receptor status) and treatment did not affect HRQOL. CONCLUSIONS HRQOL was similar between BCS and women of the general population. Potential long-term effects of breast cancer (low/high risk, receptor status) and treatment did not seem to impact HRQOL. However, predictors for worse HRQOL in BCS were being single, and having a short education.