The use of chemical fertilizers and control of pests/diseases and weeds in the management of oil palm plantations, besides causing very high production costs, is also feared to have a negative impact on the environment. Therefore and in the context of fulfilling the world community’s demands, “management of oil palm plantations that optimize the use of biodiversity” is a non-negotiable decision choice. This paper is a synthesis of research that has been carried out in 8 oil palm plantations spread across the provinces of Riau. The results showed that in the oil palm agrosystem found between 3 - 9 species of mammals (Macaca fascicularis; Macaca nemestrina, Presbytis cristata, Prionailurus bengalensis, etc.). The potential roles of several types of mammals are as pollinators (Callosciurus notatus); as seed dispersers (Paradoxurus hemaphroditus), and as pest control (Prionailurus bengalensis). Further research is needed to examine the role of each mammal species in oil palm agrosystems.