Abstract: Urban expansion is the main characteristic of urbanization. The study of urban expansion law provides decision-making basis for urban spatial planning and high-quality development. In this paper, we select Wuhan as the study area, and take the results of geographical national conditions survey from 2015 to 2018 as the main data source, the characteristics of urban expansion and ecological pattern change in the study area are analyzed by data collation and extraction, urban expansion index calculation, urban pattern change extraction and ecological landscape index calculation. The results show that Wuhan's rapid expansion from 2015 to 2018 slowed and its compactness declined. The expansion of central cities is mainly at the expense of the destruction of cultivated land. The forest and grass area in far-away district is expanding rapidly at the expense of decreasing. In the ecological index, the fragmentation of each ecological landscape type decreased, but the water area maintained well.

Key words: urban expansion, geographical condition survey, ecological pattern, geographical condition data, Wuhan