Abstract: As an important region that stretches across the eastern, central and western regions of China, exploring its temporal and spatial characteristics of high-quality development, which exerts great significance on promoting the high-quality development of the country.Based on the panel data of 108 cities in the Yangtze River Economic Belt from 2005 to 2018,this paper first creates an evaluation index system that includes fundamentals of development, social outcomes of development, ecological outcomes of development,and applys the entropy method to calculate its high-quality development level. Then, the spatial imbalance, regional disparity and dynamic evolution trend of high-quality urban development in the Yangtze River Economic Belt are systematically investigated by GIS visualization, Dagum Gini coefficient, kernel density estimation and spatial Markov chain.The results show that: (1) The high-quality urban development level in the Yangtze River Economic Belt has shown an obvious upward trend, and the spatial distribution pattern of high-level agglomeration has evolved from lower reaches to middle and lower reaches;(2) The spatial difference of high-quality urban development is distinct, of which the internal disparity in the lower reaches is the largest, while the disparity between the middle-lower reaches is the largest. During the study period,the overlapping phenomenon of high-quality urban development between regions is always the main source for regional disparity; (3) Without upper reaches, the absolute disparity in the high-quality urban development in the middle and lower reaches of the Yangtze River Economic Belt is expanding, and polarization phenomena exist steadily within each region; (4) Geographical background has significant effects on the high-quality urban development level in the Yangtze River Economic Belt. High (low) level neighborhoods will increase the probability of the city’s own high-quality development status shifting upwards (downwards).The study suggested that promoting the urban development of low-level and strengthing the radiative driving effect of high-level cities are the key points for high-quality urban development in the Yangtze River Economic Belt.