DNA region of chloroplast matK gene with 900bp in length was sequenced. Genetic relationship as well as the parameters of genetic distance of 15 Diterocarpaceae species belonging to 5 genera including Vatica, Shorea, Parashorea, Dipterocarpus and Hopea species in Vietnam were determined based on matK sequences. According to the obtained data, the investigated species were grouped in 2 groups, the first group includes Hopea species and Shorea roxbughii, remain species were grouped in the second group. The results showed that the species of the Hopea genus in Vietnam have very close relationship with an average genetic distance of only 0.4 percent. The study also showed the polymorphism in Shorea genus. Although there were only 3 species of Shorea genus but they were divided into 2 groups with genetic distance quite high (33 percent). Previously, Meijer (1976) and Maury-Lechon (1998) in their studies on morphology of Shorea genus indicated the high difference between the species in Shorea genus and suggested dividing Shorea genus into 3 separate groups. In this study, the results based on molecular characterization have confirmed Meijer and MauryLechon's suggestion, this is really complex genus and should have more deep research on this genus. The results also showed that the species belong to the Dipterocarpus and Vatica genera have more close relation than those of Hopea genus. the study result also showed Vatica, Dipterocarpus and some species in Shorea genus have same phylogeny branch.