Abstract: Through studying features of sedimentary and stratigraphic paleontology in Nangqian Tertiary basin,the authors point out the climate at Early Tertiary in basin is tropical-subtropical and rainy,the basin is not more than 1 000 m above sea level.The sedimentary faces and palaeogeography discover that in early basin development sedimentary assemblage is fan-braided-delta-lake which reflects tectonic active;in mature basin development the sedimentary assemblage is river-lake-delta.