Abstract: The floristic phytogeography of pteridophytes of 446 species(including varieties and forms) and 118 genera in 48 families were recorded from this region up to now.This paper discussed the pteridophytic ecology of Ailaoshan Mountain National Nature Reserve from uprightness distribution,east and west distribution and ecological types,and the conclusions were as follows:(1)The pteridophytic ecological types are affinitive with different vegetations.There are the most abundant peteridopytes in vegetations of the wet evergreen broad-leaved forest on upper slopes and the mossy dwarf forest on mountain tops among 2000-2800 m,furthermore,the epiphytes accounted for 28.5% in total species of this area.(2)There are 387 and 355 species of pteridophytes from east and west slope,moreover,295 are mutual species between two slopes;(3)The pteridophytic ecological types from Ailaoshan Mountain National Nature Reserve can be divided into 16 types according to the effects of ecological factors.The ecological features are characterized by:diversified ecological types,rich species of sciophytes,submegatherms and mesophytes,high proportions species of epiphytes,lower proportions species of mesotherms and submesotherms,xerophytes and lithophytes.