This paper aims to explore the social work profession’s mission in the circumstance of its professionalization in present China and a post-modern shift of social work in the western societies. The author tries first to apply postmodern perspectives to critically examine the various discourses on the mission of social work profession so far in the international circle. Then a configuration of postmodern social work is presented and its mission is stated tentatively by the author. The implications for reconstructing social work profession in China are also discussed. The paper concludes that the mission of social work profession can be determined on the basis of the ‘appointer-assumer’ relationship.