Analysis of plant geography is one of the important factors when studying the flora or any other biota to understand its compositional nature, making a basis for conservation orientation and variety development for animals, crops, etc. Analysis of the species in groups is based on the degree of similarities in their distribution area. Species of flora with distribution area which is more or less the same is grouped into a geographical element. Grouping of all the geographical elements of the flora ( percent) is the spectrum of geographic elements of that flora. Kim Hy Nature Reserve, Na Ri district, Bac Kan province has an area of 14,772ha. Initial surveys identified that the flora has 865 species belonging to 15 geographical elements and is divided into two groups: Endemic elements group and migratory elements group. Research results also confirmed the diversity of flora, making a basis for the conservation of biodiversity values and endemism in Kim Hy Nature Reserve.