Abstract:In order to understand the seed plant resources in Gaoligong Mountains, the seed plant flora between the southern and the northern Gaoligong Mountains were compared by using floristic theories and methods. The results showed that there were 2807 species, belonging to 192 families and 878 genera in the southern Gaoligong Mountains, and could be divided into 15 areal-types, 9 subtypes and 14 forms at species level. There were 2816 species, belonging to 172 families and 778 genera in the northern Gaoligong Mountains, could be divided into 15 areal-types, 9 subtypes and 20 forms at species level. From the differentiated degree, quantitative composition, and the ratio of palaeotropic components of families and genera, it was indicated that the southern flora was ancient and conservative, while the northern flora was young and newborn. The regression analysis showed that the southern flora and the northern flora were quite similar in geographical components, while the similarities of families and genera were gradually descending due to differentiation.