Abstract: There are 925 species of seed plants belonging to 132 families and 522 genera in Langya Mountain. Among them,there are 39 species of gymnosperm belonging to 8 families and 21 genera,886 species of angiosperm belonging to 124 families and 501 genera. Based on the analysis of geographical compositions of seed plants flora in Langya Mountain,it is indicated that geographical compositions of seed plants flora are comparatively complex and the transition feature is evident. 132 families can be divided into 15 areal types,522 genera into 15 areal types and 14 areal subtypes in Langya Mountain. This flora has the characteristics of the temperate zone. According to the cluster analysis, the conclusion is acquired that the flora has a close relationship with those of Qingliangfeng, MazongIing, Longqishan and Gutianshan in seven relevant mountains.