Abstract: As one of the most prominent problems in the interweaving of social economy and ecological environment in the karst area of southwest China, rocky desertification has been a hot and difficult topic in the academic circles for a long time. How to scientifically understand the temporal and spatial evolution of karst rocky desertification and its driving mechanism is the primary premise and key to karst rocky desertification control. Taking Landsat TM/OLI remote sensing images from 1987 to 2020 as the main data source, combined with remote sensing, GIS technology and geographical detector method, the spatial-temporal dynamic evolution characteristics of rocky desertification in Qujing City of Yunnan Province in the past 30 years were analyzed, and the driving mechanism of rocky desertification evolution was quantitatively explored. The results show that: (1) During 1987-2020, the area proportions of potential, mild, moderate, severe and extreme heavy rocky desertification in Qujing City decreased from 8.56%, 9.71%, 4.85%, 0.98% and 0.35% to 8.35%, 9.29%, 4.32%, 0.79% and 0.29%, respectively. Among them, the area proportion of potential, mild and moderate rocky desertification fluctuated, and the annual change rates were 0.16%, -0.22% and -0.19%, respectively. The average annual change rates of severe and extreme rocky desertification were -0.56% and -0.32%, respectively; (2) Rocky desertification in Qujing City is large in area and wide in distribution. mainly distributed in the peak cluster depressions, hills, dry-hot valleys and the inter-county boundary regions. The overall pattern of rocky desertification is severe in the southeast, mild in the middle and northwest. (3) The main single factors affecting the development and evolution of rocky desertification in Qujing City were the gross agricultural output value (0.281) and the cultivated land area (0.233). Interactive detector further reveals that the slope ∩ cultivated land area (q=0.465) > cultivated land area ∩ total population (q=0.374) > cultivated land area ∩ population density (q=0.302) > average annual precipitation ∩ slope (0.283) > cultivated land area ∩ distance from settlements (q=0.278), the interaction effects of driving factors on rocky desertification evolution is greater than that of the influence of single factor effect, showing the karst rocky desertification of Qujing City is the result of the interaction of multiple driving factors.