Mainland China adopts foreign aid, through which it accomplish its diplomatic goal, as the main policy tool for its economic diplomacy. In this dissertation , I intend to sort it out and analyze the process of its policy-making and give a clear picture of the evolution of its economic diplomacy. Through my analysis of Mainland China's foreign aid policy , one can tell the development of Mainland China's economic diplomacy which had gone through five phases - "ideological economic diplomacy", "contact economic diplomacy", "integrated economic diplomacy", "participatory economic diplomacy", and "leading economic diplomacy".