The fossil plants studied  in  this  paper  were  collected  from the Upper  Carboniferous and Permian in  Liujiang Basin, Hebei  Province. This  flora was composed of 86 species in 44 genera  belonging to Filicopsida (41.8%), Cycadopsida  (4.6%), Cordaitopsida  (2.3%), Ginkgopsida (2.3%)  and  Coniferae  2.3%.x Many fossil plants had  the characteristics of Cathaysia flora.  The  flora could be divided into six assemblages in ascending order:Linoptleris neuropleroides-Lepidodiendron galeatum, Neuropteris plicata-Lepidodendron posthumii, Lobatannularia sinensis-Annularia stellata, Pecopteris anderssonii-Pterophyllum daihoense, Cladophlebis permica-Psygmophyllum multipartitumand Uilmannia bronnii-Walchia bipinnata assemblages. According to the sedimentary characteristics and plant assemblages, the evolution  of the flora  could be divided into six stages. In the first stage(Benxi Formation) deep subtidal，lagoon,delta and river occurred allernativelyIn the second stage (Taiyuan  Formation), subtidal，tidal flat and delta occurred alternativelyIn the third stage (Shanxi Formation), swamp, distributary channel, natural levee,and crevasse splay occurred alternatively. In the fourth stage (Lower Shihezi Formation), swamp, distributary channel, and sand bar occurred alternatively. In the fifth satge(Upper Shihezi Formation), large lake lake, natural levee,and river mouth bar changed to point bars and central bars. In the sixth stage(Shiqianfeng Formation), large lake delta, natural levee, river mouth bar and point bar ocurred alternatively.Key wordsLiujiang Basin, Carboniferous,Permian, Cathaysia flora, evolution  of paleaogeographyAbout the authorYang Tongsheng，born in  1958，graduated  from China  University of Geosciences(Beijing) and  obtained Ph. D. degree in 1999.Now he is an  associate  professor,and   is  engaged in paleobotany，sedimentary  environments  and  paleoecology.