The most recent Danish health survey of 2005 is based on a region-stratified random sample of 10.916 individuals. Data were collected via personal interviews and self-administrated questionnaires. Respondents suffering from chronic pain were identified through the question 'Do you have chronic/long-lasting pain lasting 6 months or more?' The prevalence of chronic pain among individuals with a present or earlier cancer diagnosis was also assessed. In all, 7275 individuals (66.6%) completed a personal interview and 5552 individuals (50.9% of the original sample) completed and returned the self-administrated questionnaire. The same questions were included in the survey in 2000 and, hence, it was possible to evaluate the trends in the past five years. In all, 20.2% of the adult Danish population has chronic pain. From year 2000-2005 the prevalence of chronic pain has remained stable. Generally, chronic pain was associated with female gender and increasing age. Higher prevalence of chronic pain were associated with being divorced, separated or widowed, having less than 10 years of education and high BMI. Musculoskeletal diseases (66.8%) were the most common cause for chronic pain and most persons with chronic pain rated their health and quality of life as poor. Persons with earlier or present cancer diagnosis were more likely to report chronic pain. A substantial part of persons with chronic pain were not satisfied with the examinations and treatments offered. In conclusion, over a five-year period the prevalence of chronic pain in Denmark has remained stable, but high.