Abstract: A fossil leaf described here was collected from the fourth layer (Interbedding of black carbonaceous clay and grey fine sand with clear texture of microstratification), section D of fossil ape locality in Lufeng, Yunnan, in 1981. Dryophyllum relongtanense is an extinct type. It is a special form of early Tertiary. The leaf is narrow, the nervation is the same as Quercus and Castanea except for the form of the leaf. Dryophyllum is closely allied in the leaf architecture to Castanea, Lithocarpus and Castanopsis. This genus appeared in the early Tertiary in northeast China and North America. The specimens of Dryophyllum relongtanense were collected from several lignite basins in Miocene, central Yunnan, and also appeared in the Shuanghe coal series in Jianchuan, northeastern Yunnan, it was always discovered along with Fagaceae, Lauraceae and Ficus in the same beds and this assemblage indicated that the climate was warm and humid like the subtropic zone.