Assessing the experience and impact of pain in adolescents with chronic pain is necessary to guide both individual treatment and to inform treatment development. Ideally, to obtain a comprehensive understanding of the impact of pain, assessment should be multidimensional, should be sensitive to contextual variables, and should allow for multiple informants (in particular, parents). The purpose of this study was to develop a standardized parent-report measure of chronic pain in adolescents, the Bath Adolescent Pain Questionnaire – Parent report (BAPQ-P). Participants included 222 adolescents with chronic pain and their parents recruited from two specialty clinics in the UK. The adolescents completed a battery of self-report inventories related to their pain and daily functioning whilst parents completed the BAPQ-P and additional measures of adolescent functioning. Scales of the BAPQ-P emerged to be internally consistent and temporally stable over a 17-day period. Validity was examined in relation to existing validated child report measures of anxiety, depression, catastrophizing, disability, family, and social functioning and parent report measures of disability and family functioning. Psychometric evaluation suggests that the BAPQ-P is a reliable and valid parental report tool for assessing the multidimensional impact of adolescent chronic pain. It can be used in conjunction with the previously established adolescent self-report measure, the BAPQ, alone where adolescent self report is not possible, in studies where parent report is the focus, or in studies where concordance between parent and adolescent reports is of interest.