Binh Chau-Phuoc Buu Nature Reserve was established in 1996 with total area of about 11.293ha. This Nature Reserve is located in Southern Coastal Dipterocarp Lowlands region which was determined by WWF as one of the crucial priority sites for conservation. Le Xuan Canh et al. (2000) reported 49 mammal species occuring in this Nature Reserve, including some endangered species such as Sun bear Helarotos, malayanus and Silvered langur Trachypithecus margarita. However, the occurence status of many species. is still uncertain, for example the jungle cat Felis chaus, golden cat F. temmincki, and leopard Panthera parelus. In order to review the mammal fauna of the Nature Reserve, the authors conducted an intensive inventory from August 2011 to June 2012, using proper methods for each mammal taxonomic group. The authors recorded 30 mammal species, including new records of 11 mammal species for the Reserve. However, six species were removed from the mammals list because of unsuitable habitat and distribution range. There are 11 species that are listed in Vietnam Red Data Book and 04 species listed in 2011 IUCN Red List of Threatened Species. The mammal fauna of the Nature Reserve are facing many threats not only from human activities but also from internal condition.