Abstract: Based on DMSP/OLS, NPP/VIRS nighttime lighting data, and SPOT/VEGETATION NDVI data, the spatial development mode and vegetation change characteristics of urban built-up areas in Chengdu-Chongqing area were studied, which provided reference for the optimization of urban layout and the maintenance of regional ecosystem. The boundary of urban built-up area in Chengdu-Chongqing area was extracted by statistical data comparison method, and the urban development was analyzed from the aspects of urban expansion characteristics and speed. Taking NDVI as an indicator of the vegetation status in urban built-up areas, the vegetation changes in Chengdu-Chongqing area from 2001 to 2020 were studied from the aspects of NDVI total, mean, interannual change rate, change percentage, and coefficient of variation. The results showed that the accuracy of the built-up areas extracted using statistical data comparison method was relatively high, and the error rate was less than 2%. The annual average speed of urban expansion was on the rise, and the urban expansion speed from 2015 to 2020 was 12.23 km²·a⁻¹. The total NDVI of urban built-up areas first increased and then decreased with the increase of built-up areas. The vegetation condition improved from 2001 to 2010, but the vegetation began to deteriorate from 2010 to 2020. The vegetation condition in urban built-up areas was generally worse than that in background areas. The vegetation stability in urban built-up areas was poor, and the urban coefficient of variation increased in different degrees over the past 19 years.