Acceptance of pain and distress has lately appeared as an important factor in determining peoples' ability to restore functioning in the presence of chronic pain. Although treatments based on cognitive behaviour therapy are beginning to incorporate acceptance strategies, there is still a lack of reliable and valid instruments to assess relevant processes in such interventions. The Chronic Pain Acceptance Questionnaire (CPAQ) was originally constructed as part of the development of an acceptance oriented treatment approach for pain patients. A revised 20-item version of the instrument with two subscales has shown adequate reliability and validity. In the present study, a Swedish translation of CPAQ was evaluated with 611 participants reporting chronic pain and symptoms of whiplash associated disorders. This study sought to further assess the psychometric properties of the instrument and to investigate its relation to another important measure of pain adjustment, the Tampa Scale of Kinesiophobia. Due to low intercorrelations with other items, item 16 was excluded. Exploratory and confirmatory factor analyses supported the previously suggested two-factor solution. Furthermore, the internal consistencies were good for the subscales (activities engagement and pain willingness) as well as the total scale. Hierarchical regression analyses illustrated strong relations with criteria variables (e.g. disability and life satisfaction). In general, the activities engagement subscale contributed more than pain willingness to the prediction of criteria variables. Furthermore, results illustrated that CPAQ explained more variance than the Tampa Scale of Kinesiophobia in pain intensity, disability, life satisfaction, and depression.