Abstract: Land development degree (LDD) has been a useful approach for measuring the extent to which human activities have influenced the land development. The analysis of spatiotemporal differences and driving factors of land development degree contribute to a deeper understanding on the relationship between human activities and regional land utilization, which provides mechanistic information for formulating different regulation policy for regional land use. The study analyzed the spatial pattern of land development in 345 cities and discovered the driving factors of LDD by using geographical detector. The results showed that China’s LDD has increased from 4.1% to 4.47% between 2009 and 2015. The LDD of 345 cities have increased generally and presented significant spatiotemporal differences among the three economic regions. Cities with high LDD were concentrated mainly in megalopolis, which grew faster in Yangtze river delta and the Silk Road Economic Belt. The main driving factors for LDD have changed from investment and population to industry and population at the national scale. The influence of these factors also varies in different regions. In eastern region, population and industry have driven the LDD instead of investment and industry; population was the main driver of LDD in central region; while the investment played an increasingly important role in western region.