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Understanding spatio-temporal changes of urban environments is essential for local planning and environmental management. In this study, Landsat TM/OLI images covering Luoyang region were used as the main data source. The method of spectral indices was used to extract impervious surfaces in 1990 and 2016. The results show that the area of impervious surfaces in Luoyang showed a rapid increase trend, from 62.77 km2 in 1990 (accounting for 7.79% of the total area of the study area) to 149.37 km2 in 2016 (accounting for 18.55%). Luolong District has the largest impervious surface area change, followed by Yibin Development Zone and Jianxi District, while old cities of Laocheng District, Xigong District and Chanhe District have not changed much. The establishment of Luolong New District in 2000 gradually shifted Luoyang's urban center from the north bank of Luohe River to the south bank, forming a rapid growth of urban construction land in Luolong District from 2000 to 2010. Old cities mainly expanded northward to varying degrees, and its road network has a rapid growth in the surrounding area. Yibin Development Zone was a remote, small population village in 1990, and recently it has become a new urban expansion area. The main driving forces of changes in impervious surfaces in Luoyang include natural and geographical conditions such as topography, and tourist resources, and the policy as one dominant factor controlling the spatial pattern of impervious surface expansions in Luoyang City.
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