There has been a wide recognition that middle-level administration is an important part in regional capacity building for sustainable development (CBSD). After reviewing and assessing the common connotation of CBSD,the paper discusses the evaluation of regional CBSD, with an emphasis on basic principles and main thoughts insisted by middle-level administration for regional CBSD. The paper indicates public policy process optimization and stressing the self-improvement of government are main approaches to enhance regional CBSD. Knowledge management (KM) and information sharing mechanisms can facilitate effective participation and promote CBSD. At last the paper builds the circulative model of sustainable development policy formulation, practices and optimization on the basis of "problem-countermeasure-response".