Urban development causes various environmental cost, such as carbon dioxide emission, solid waste, and resource consumption. While life cycle analysis studies are attempted, their interactive linkage with social policy elements are seldom analyzed. In this paper, firstly, environmental emission structure from urban development projects are generally discussed. Secondly, the scheme of estimation program is shown, which has multi-system structure. Thirdly, estimation process is presented. Finally, case study is done in Nakanoshima District, in the Osaka City downtown, Japan. The following are found, (1) operation process counts for a large part of carbon dioxide emission in the urban facility life cycle.(2) denser building location cause carbon dioxide emission increase from the district.(3) combination of facility-scale and district-scale improvement can be effective countermeasures for environmental lord reduction.