The forest ecosystem of South-western Côte d'Ivoire harbors an exceptional biological diversity with numerous endemic species. This region is characterized by the existence of many agro-industrial plantations that constitute a real threat the survival its extraordinary biodiversity. The remaining forest relics within these vast plantations constitutes the only hope of local fauna maintaining and surviving. This study aimed to assess the biological diversity and conservation status of Mammals in four forest relics within the agro-industrial plantations of SOGB Company. Tracks, sound and visual observations were used to survey the presence of Mammals. The presence of 31 Mammal species was confirmed in these forest relics. Of these Mammals, one is listed as Endangered (EN), two are classified as Vulnerable (VU) and three are Near Threatened according to the International Union for the Conservation of Nature (IUCN) criteria’s. The forest relics sampled contained a large proportion of the characteristic Mammal fauna of the Upper Guinean forests and six species shortlisted on IUCN’s red list of threatened species, which give them a high conservation value and the need of immediate protection.