Background Pterocarpus erinaceus Poir. is a spontaneous species from the three ecological zones of Benin. It is multipurpose species integrated to the socio-economic and cultural livelihood of populations, especially in rural areas. This study examined the different uses made of the organs of Pterocarpus erinaceus in Benin in relation to sociolinguistic diversity with a view to highlighting the knowledge of local populations on Pterocarpus erinaceus and the threats to the species. Methods A total of 355 respondents, spread over 18 townships in Benin, were interviewed using a questionnaire. About 57 uses shared into 7 categories of use have been identified from the different sociolinguistic and socio-professional groups. Relative citation frequencies (FRC) of each habitat were then calculated for the description of habitat variation according to Ecological zones (EZ). In order to describe the diversification of the categories of uses and the organs / part of the tree, Principal component analyzes are carried out on the matrices comprising relative citation frequencies (FRC) grouping together the socio-demographic factors and the categories of use under the packages FactoMineR and factoextra Results This study revelated that the wood of Pterocarpus erinaceus is used (25.43%) in crafts, as charcoal, and service wood, while the leaves are mainly used (23.14%) as fodder and by traditional medecine. Concerning the roots and bark, they are used (27.14%) not only for evil spirits and bewitchment but also in animal medecine in cattle. About 60 diseases and symptoms are cured by the various organs of Pterocarpus erinaceus. These different uses of Pterocarpus erinaceus varied from one sociolinguistic group to another. Conclusion The study showed that all organs of Pterocarpus erinaceus are used in various forms of use for various purposes and make it an important species for rural communities. This result suggests the need to define conservation strategies for natural stands of Pterocarpus erinaceus for the sustainable management of the species.