Abstract: On the basis of a detailed study of the Late Paleozoic section in the Bogexi area, Batang county, western Sichuan, six lithostratigraphic formations may be recognized in the study area. According to the conodont and fusulinid fossils, their ages are determined to be Devonian Permian. The stratigraphic sequences in the area are successively （in ascending order） as follows: the Yazigou Formation , which uses the name of the Muli district; the Bogexi Formation and Longba Formation ,whose connotations have been revised; the Duogei Formation and Duogei Formation , which is newly established. The Late Paleozoic lithostratigraphic system in the Taocheng has been preliminarily set up and perfected.