We present the results of a rapid ecological assessment conducted in 2012 in the community of Boanamo, in the Waorani Ethnic Reserve and Yasuní National Park, Orellana and Pastaza provinces, Ecuadorian Amazon. The study included surveys and observations of mammals by different methodologies over a 16-day sampling period. The results show the presence of 89 species of mammals, but there are several other mammal species expected in the area, increasing the projected diversity to 119 species, a high diverse community when compared with similar locations. Statistical analyses show that Boanamo is an area of high species richness and heterogeneity, consistent with comparable surveys in other areas of primary lowland rainforest in Amazonia. In addition, we documented nine distinct ways and 130 different usages in which 43 species are utilized in Boanamo. To estimate the importance of mammal diversity, we used a Cultural Importance Index, which shows that the species with the highest value are Panthera onca and Nasua nasua. However, the most frequently hunted species were Tayassu pecari and Lagothrix lagothricha. Our final conclusion is the community of Boanamo is entirely dependent on the surrounding forest, and mammals are an important part of their culture and subsistence.