The spatial distribution of plant diversity in Dong Na Tard Provincial Protected Area (PPA) has not been accurately recorded in previously published literature. This study was conducted to assess and evaluate plant species and its correlation with environmental variables. Plot methods coupled with informal community folk interviews were done. Cluster analysis indicated six forest zones which were classified based on Relative Basal Area (RBA) of dominant species. The species composition in each forest zone was significantly influenced by slope, elevation, human disturbance, and distance from the main road to a dense forest. Dipterocarp forests were the most dominance and should be conserved in sustainable manner.