The creation of biosphere reserves is one of the strategies adopted to ensure the conservation of biodiversity. Despite this provision, the effectiveness of biosphere reserves in ensuring the conservation of biodiversity is still a subject of scientific discussion. This study aimed to analyze the effectiveness of the Mono biosphere reserve in Benin in the conservation of endangered woody species. Maximum entropy modeling (MaxEnt) was carried out to identify the favorable habitats of these endangered woody species. Habitats favorable to the various endangered woody species were then superimposed on existing ACCBs to determine the proportion of favorable habitats found in these ACCBs. The results revealed conservation gaps in the Mono Biosphere Reserve, as more than 86% of the habitats favorable to endangered woody species were located outside the central area and buffer zone of the reserve where conservation efforts were concentrated. Based on these results, it is necessary to generate new core areas from the appropriate habitats of endangered woody species to reduce conservation gaps in the Mono Biosphere Reserve.