Abstract: The laterite-forming capacity of carbonate rocks is an important problem in investigating development and evolution history of the karst morphology. This paper studies the carbonate rocks sections，their laterite formation by weathering, and distribution of underlain Permian-Triassic-Jurassic sediments in Jinyang District, Guiyang City, Guizhou Province. Combining with development features, thicknesses and lithologies of the strata, and the empirical values of laterite formation for carbonate rocks, the thickness of laterite in the research district is estimated. By comparison of the theoretical laterite thickness with the practical preserved laterite thickness, it is deduced that the present day preserved laterite layer is the weathering product of the third peneplanation stage since the Early Pleistocene. Its formation age is about 400 ~1 300 ka. Our results show that the present day preserved laterite layer overlying carbonate rocks is not only weathering product of the carbonate rocks, but also of their clastic rocks interlayers which make considerable part of the laterite soil. Moreover, the Jurassic (containing no carbonates) clastic sediments were also important original rocks for laterite formation. Consequently, the sources of laterite formation in the study district were multiple and complex, but not the carbonates solely.