Abstract: The Panxi area lies in the intermediate zone between the Sichuan basin and the central Yunnan basin. Cretaceous red beds are well developed. For lack of paleontological evidence, the problem of the stratigraphic division and age has not yet been solved for a long time. In rccent years abundant charophytes fossils have been found during 1:50000 regional surveys. Preliminary study shows that: the Datongchang Formation is characterized by the occurrence of the Mesochara stipitata-M. paragranulifer-Actistochara mundula assemblage, including 15 genera and 41 species, whose age is late Early to early Middle Cretaceous（late Barremian-Aptian）;the charophtyes of the Xiaoba Formation are monotonus in composition and simple in structure and are characterized by the Obtusochara huiliensis-O.huicongensis assemblage, which displays a strong endemic colour. whose age is roughly middle to late Middle Cretaceous（Cenomanian-Turonian）.