Introduction: The Management of Biomedical Waste (MBW), needs the involvement and the action of professional or social entities in relationship with health facilities. This study aims to assess the involvement level of Patients and their Accompanying persons (PA) in the MBW. Methods: It was a cross-sectional and analytic study made on 409 PA hired by their commodities, in six health facilities in Benin. Data were collected through a survey on sociodemographic characteristics, type of waste, knowledge and perception of PA on the MBW, the access to storage places and perceptions on health and environment in link with the MBW. The data were entered and treated by Epidata and the software R 4.1.1.1. The proportions were compared with the Chi-square test. Results: At the univariate analysis, the health facility, the gender and the knowledge of the storage place were associated to the involvement of PA in the MBW. The access to the storage places were associated to the health facility, the profession and the knowledge of storage places. The PA that knew the storage place of BW were more than seven times at risk of been involved in the MBW compared to the others. Conclusion: 26.9 % of PA have access to the storage place of BW. Regarding the potential infectious risk that could induct this practice for PA, it is necessary to improve the management system of BW and sensitize the PA.