Abstract: By extracting and correcting DMSP/OLS and NPP/VIIRS nighttime light data, this paper measures the economic development level of the Yangtze River Economic Zone in a long time series. The coupling coordination degree model is used to calculate the coupling coordination between economic development and eco-environmental carrying capacity of the Yangtze River Economic Zone, and its spatial-temporal variation, regional difference and spatial spillover effect are analyzed. The results show that the degree of coupling coordination increases steadily from moderate imbalance stage to antagonistic stage from 1998 to 2019. In terms of regional difference, the overall spatial difference of coupling coordination level is in the process of continuous adjustment of “convergence-differentiation-convergence”. The overall spatial difference is mainly derived from the inter-regional differences, and the inter-regional differences are mainly from the differences between upstream and downstream of the Yangtze River Economic Zone. In the spatial pattern, the coupling coordination level shows a significant spatial agglomeration effect, and 11 provinces show a trend of multi-polar differentiation. By analyzing the spillover effect of coupling coordination level, it is found that the degree of wealth, innovation investment, foreign investment and environmental regulation are beneficial to the improvement of local coupling coordination level, and industrial structure and population scale have a significant inhibitory effect on the local coupling coordination level. Industrial structure, foreign investment and population scale promote the coupling coordination level of adjacent areas through positive spillover effect.