City is a social-economic-natural complex ecosystem. In this paper,according to the level of the relationships between material flow, energy flow and information flow, also by taking their properties as indexes, Changchun city was divided into 48 land ecotypes and 8 land ecoregion in light of the features of their associations, Each ecoregion has its own characteristics, and the ecoproblems are defferent. On the basis of imitateng the type of nature, each land ecoregion was designed following the principle of making concordant relationship beween human and nature. In the end, we should build up an ideal city which would be in conformity with the human benefits as well as the organization principle of the biosphere.