Abstract: Seven 3rd-order cycles of continuous sea--level changes from the late Luodian Stage to the Lengwu Stage(Permian)in the platform area of southern Guizhou Province are recognized based on the characteristics of sequence stratigraphy in the study area．The process of regional sea-level changes could be divided into two stages，of which the first stage includes 1st～3rd cycles characterized by lower rote of early rise；and the second stage includes 4th ～7th cycles characterized by higher rote of early rise．Among these cycles，early-rise rotes in the first cycle and the fourth cycle were the lowest and highest，respectively．Although the sea surface in the process of sea-level changes was always high up the shelf break，the last sea-level fall accompanied by the Dongwu crustal movement at the end of Lengwu Stage caused overall regression and exposure of the area．The study results show that the evolutionary pattern of fusulinacean foraminifera (Middle Permian)in this area might be related to above mentioned sea-level changes．