Abstract: Taking 11 provinces (cities) in the Yangtze River Economic Belt as the research object, the AHP-entropy method combining subjective and objective evaluation, relative development model and coupled coordination model were used to analyse the spatial and temporal differentiation characteristics of the coupled coordination of new urbanisation and high-quality development in the Yangtze River Economic Belt from 2000 to 2020, and the geographical probe was used to explore its The results show that: the Yangtze River Economic Zone has a high level of urbanization and high quality development. The results show that: 1) The level of new urbanisation and high quality development in the Yangtze River Economic Zone showed a steady growth in general during the study period, with a slow to fast growth rate before levelling off and an uneven spatial distribution regionally. 2) The degree of coupling and coordination between new urbanization and high-quality development in the Yangtze River Economic Zone has undergone a transformation from antagonism to friction to coordination, with the development trend constantly improving, and there are obvious spatial differences in the state of coupling and coordination between regions. 3) There are obvious dynamic changes in the coupled and coordinated state of new urbanization and high-quality development in the provinces and municipalities in the region, with Guizhou showing the greatest inter-annual variation and Zhejiang, Jiangsu and Shanghai being more stable. 4) The effects of urban population density, urban-rural disposable income ratio and population urbanisation rate on the differences in the coupled and coordinated levels of new urbanisation and high-quality development in the Yangtze River Economic Zone are somewhat robust, with the other factors having varying magnitudes of explanatory power and inter-annual variation.