In this article, we investigate the biocultural behavior regarding the use of species of the Euphorbiaceae in the Franco community, Cocal, Piauí State, located in the Semiarid Region of Brazil. For the study, we performed 19 interviews with the home gardens maintainers based on semi-structured interviews, and calculate the Use Value (UV) for each species mentioned by the interviewees. In addition, the importance of socioeconomic factors in this type of biocultural behavior was evaluated. Seven species of the Euphorbiaceae with biocultural emphasis were mentioned, distributed across four genera, which are cultivated for various purposes, including food, medicine, fuel, animal fodder, commercial sale, cultural uses, and others. The species Ricinus communis (“mamona”) presented the highest UV (7.0). Socioeconomic factors did not influence biocultural behavior associated with the use of plants of the botanical family studied. Our findings suggest that documented biocultural attitudes are essential to ensuring the resilience and conservation of biological and cultural diversity.