Species richness and distribution are closely related to topography factors (altitude, slope grade, slope aspect, slope position), and study their relationship of Qizimei Mountains Nature Reserve is important to maintain and restore the plant diversity and the management of forest. Phytosociological method was used to investigate plant communities in Qizimei Mountains Nature Reserve. Furthermore, the regression analysis and canonical correspondence analysis were used to study the effect of topography on species richness and distribution pattern. The results showed that: (1) there were 633 plant species and it was belonging to 133 families and 316 genera. And it contained 118 species of trees, 150 species of shrubs and 365 species of herbs in 40 sample plots(20×20 m²). (2) The results of curve fitting indicated that the species richness was highly significantly correlated to altitude and slope (P＜0.05), the species richness increase with increasing altitude and had a tendency with slope gradient that was after reducing first increase and then decrease. (3) The plant life form showed, at all altitudes, tree species richness was consistently lower than that of shrubs and herbs. Moreover, shrub species richness was higher than that of trees and herbs in low and midlow altitude zones. Besides, species richness of herbs in middle and high altitude areas was larger and higher than that of trees and shrubs. (4) Canonical correspondence analysis showed that the topographic factors had a great effect on species distribution (P = 0.002＜0.01) , and according to the impact intensity ranked as altitude＞slope＞slope position＞slope aspect, which indicated that altitude is the most significant factor for affecting the distribution of species in Qizimei Mountains Nature Reserve.