Urbanization is a key issue of current social development. The expansion of urban construction land is one of the most important forms of urbanization. Research on urban construction land in typical regions can provide important data support for urban planning and scientific development in local and similar regions . Based on the 2010-2018 natural, social, and economic data of Liangjiang New District, Chongqing City, using principal component analysis methods, geographic detectors and other methods to analyze the spatio-temporal changes of urban construction land in Liangjiang New Area, the research results show that Liangjiang New Area urban construction land expansion trend is rapid first and then slow; the expansion area is concentrated in the "four mountains and troughs" and along the Jialing River, the main source of urban construction land is cultivated land, and a small part of woodland and garden land; the main time driving factors for expansion are the GDP value and the proportion of the secondary industry, and the main spatial driving factors are rivers, slopes, distances from administrative centers and major highways. The expansion of urban construction land is affected by many factors. In the long-term series, it is mainly affected by economic factors, and spatially affected by natural factors.