Anurans are subject to strong anthropic pressures in Benin, as in most of the West African countries, due to their socio-economic and environmental importance. To protect these organisms and to gather basic knowledge, an anuran biodiversity study was conducted in the lower Ouémé Valley in Benin. Anurans were inventoried in five types of habitats in four municipalities. Visual and auditory detections were used to observe, count and/or catch specimens at night, aided by headlamps. Five physico-chemical parameters were simultaneously measured. Species were determined using identification keys, authenticated by specialists at the Leibniz Institute for Evolution and Biodiversity Science's Museum für Naturkunde, Berlin. Our study observed 28 species, with several species living in degraded forests. Afrixalus fulvovittatus (Cope 1860) was recorded for the first time in Benin; and the taxonomic status of three anuran species, Sclerophrys sp., Hyperolius sp. and Arthroleptis sp., still require clarification. Among the species inventoried, Hyperolius torrentis is listed as vulnerable by the IUCN category. Anuran distribution was closely related to ambient air temperature and soil humidity, with abundance increasing with low ambient air temperature and high soil humidity. We note the importance of protecting these organisms' habitats in order to maintain the optimal environment for their growth and breeding.