Carers of patients with dementia experience high levels of stress that can adversely affect their health and well-being. Our aim was to assess the health-related quality of life of carers of patients with dementia compared with an age- and gender-matched sample from the general population. A cross-sectional study was conducted in 37 primary health care centres in Catalonia, Spain. Carers (n = 181; 78% females, mean age 63 years) of patients with dementia together with a random sample of 543 individuals from the general population, matched for age and gender, were assessed with the SF-36 questionnaire, which is a generic measure of health status. With the exception of physical function category, seven of the scales showed lower scores for females in the carer group. The most important differences were observed in the emotional role [95% confidence interval (CI) -37.7 to -3.6], mental health (95% CI -21.0 to -1.6) and bodily pain (95% CI -37.7 to -8.6) categories. In contrast, male carers had higher scores in the physical function category (95% CI 2.2-19.4), and no differences were observed on the other scales. Female carers of patients with dementia experienced a seriously decreased quality of life level compared with their contemporaries in the general population.