The occurrence of both soil erosion and rocky desertification in karst areas of China have attracted much attention. In order to quantify the correlation between soil erosion and rocky desertification under different lithologies and to establish a basis for optimizing the area's ecosystem, the present study investigated the correlation between soil erosion and rocky desertification in Yanhe County (Guizhou Province, China) using Landsat remote-sensing data, a 1:5000 topographic map, and both lithology and rocky desertification data. Supervised classification, surface analysis, and grid calculation were used to extract a variety of soil erosion indices. (1) Rocky desertification affected 284.44 km² of Yanhe County, thereby accounting for 11.52% of the county's total land area, and the grade of rocky desertification was mild, moderate, and strong. Meanwhile, soil erosion affected 1838.97 km², thereby accounting for 74.48% of the county's total land area, and the grade of soil erosion was mostly mild, moderate, and intense. (2) Both rocky desertification and soil erosion were predominant in the interbedded and continuous limestone and clastic rock, with 57.99% and 50.45% of the rocky desertification and soil erosion found in this area, respectively.(3) Non-carbonate rocks, limestone clastic rocks, limestone and dolomite mixtures, limestone and clastic interbeds, continuous dolomite and limestone, rocky desertification grade, and degree of soil erosion were all negatively correlated with mild, positively correlated with Light and moderate rocky desertification, and negatively correlated with moderate and extremely severe rocky desertification. Soil erosion grade was positively correlated with rocky desertification in Potential and Light erosion. There was a negative correlation between Light and severe erosion. Among the limestone and dolomite mixtures and continuous dolomite, rocky desertification grade was negatively correlated with the degree of soil erosion.