Result of the study on medicinal plants in the Pu Luong Nature Reserve in Thanh Hoa province showed that belong to 290 species, 215 genera and 82 families of 4 divisions (Lycopodiophyta, Polypodiophyta, Pinophyta and Magnoliophyta). The largest family of epiphytes is the Magnoliophyta which comprises about 94.14 percent of all epiphytic species. The medicinal plants of Pu Luong are 9 threatened species listed in the Red Book of Vietnamese (2007). Medicinal plants in the four study areas form the main body with 89 herbaceous species, trees with 78 species of dust, woody vines 70 species and 53 species. Parts used most leaves with 136 species, 96 species roots, the lowest resins, pus and service body for three species. Recorded 16 groups of diseases are usually people in the conservation of plants used for treatment, including gastrointestinal disease group with 39 species, skin diseases group with 43 species, 33 species of disease with the weather, the lowest group of allergic diseases, disease group sweating hands and feet along with a species.