Drought is a natural phenomenon of the global widespread occurrence, while Karst drought can not simply be attributed to the climate anomalies, reduced-rainfall. In this paper, 40 typical watersheds in Guizhou Province were selected as the sample areas, the soil water body index (SWBI) was built by using object-oriented classification techniques, to extract the remote sensing information of land-using types. To calculate the landscape density index (PD), largest patch index (LPI), shape index (SI), and landscape fractal dimension index (FDI) of the land -using types by using the calculation software of landscape indices (Fragstats4.0), and analyze the spatial distribution pattern of land-using types. To explore the variation of watershed storage-space under the different land-using patterns, the sizes of watershed water-storing capacity, and study the affect of land-using types and its spatial change on hydrologic droughts. The study has shown that: (1) The distributions of woodland, dry and shrubbery are relatively concentrated, the larger the spatial variation, and that of water and urban is relatively dispersed, the smaller the spatial variation; (2) The affects of the plaque density and largest patch distributions of land-using types on hydrologic droughts are larger, and the smaller the patch edge and patch shape distributions of land-using types; (3) The larger the patch density index, largest patch index, patch shape index and plaque fractal dimension index of land-using types, the smaller the affects of land-using types on hydrologic droughts.