Community health workers (CHWs) play a crucial role in HIV/AIDS prevention programmes targeting female sex workers (FSW). In Kinshasa and Nigeria, CHWs have been instrumental in delivering evidence-based interventions aimed at reducing risk behaviors among FSW. A longitudinal mixed-methods approach was employed, combining quantitative data from surveys with qualitative insights gathered through interviews and focus groups. Data collection occurred at baseline () and follow-ups every six months until the end of in Nigeria and for Kinshasa. Significant reductions were observed in high-risk sexual behaviors among FSW, with a decrease of 45% in unprotected sex practices over two years. There was also an increase in knowledge about HIV/AIDS prevention strategies from baseline to follow-ups (p < 0.01). The community health worker programme significantly improved the risk reduction strategies and knowledge levels among FSW, indicating a promising strategy for HIV/AIDS prevention. Continuation of CHW programmes with enhanced training and support is recommended to sustain the observed improvements in behaviour and knowledge. Further research should explore scalability and cost-effectiveness across different settings. HIV/AIDS, Female Sex Workers, Community Health Workers, Prevention Programmes, Kinshasa, Nigeria