During June 2008 to June 2010,165 butterflies species (Rhopalocera) were determined, belonging to 10 families of Lepidoptera. the authors also described biological and ecological characteristics of 8 rare and precious species in Pu Huong nature reserve. They are: Troides helena, Papilio noblei, Lamproptera curius, Byasa crassipes, Attacus atlas, Hebomoia glaucippe, Thaumantis diores and Thauria lathyi. Among these species, 5 species are listed In the Red Data Book of Vietnam in 2000 and 2007.