Drawing in research results through screening the policy content, background and effect of the Obama Administration’s DPRK policy, this paper structures a quadrennial framework from multilateral, alliance, U.S.-China relations and unilateral perspectives to summarize main contents of the Obama’s DPRK policy; in terms of understanding its decision-making process, the paper brings in the environmental policy factor, and hopes to comprehensively explain reasons for the Obama Administration’s DPRK policy through exploring the emerging new culture on Korean Peninsula and in Northeast Asian region, and comes up with some observations on an impact of Obama’s DPRK policy on China’s security.