BACKGROUND: Ensuring uninterrupted HIV treatment for female sex workers (FSWs), who face a disproportionately high HIV burden, is crucial for curbing HIV transmission and disease. Structural, social, and legal barriers impede their access to HIV services. The differentiated service delivery (DSD) model, designed to tailor and decentralise HIV services, aims to overcome these barriers. However, the impact of the DSD model for HIV treatment uptake among FSWs in sub-Saharan Africa (SSA) is not well documented. OBJECTIVES: To assess the implementation of the DSD model in improving HIV treatment outcomes among FSWs in SSA. METHOD: A systematic review literature was conducted to include available records from January 2019 to March 2024, using electronic databases such as EBSCOhost, Science Direct, SCOPUS, PubMed Central, and others. Ten studies met the eligibility criteria for inclusion for the review. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and was registered with the International Prospective Register of Systematic Reviews (ID: CRD42023440551). RESULTS: The uptake of HIV treatment services varied depending on whether the DSD model was facility-based, community-based, or a combination of both. Community-based models were generally preferred and led to better treatment outcomes due to their comprehensive health services. CONCLUSION: To improve HIV treatment outcomes for FSWs in SSA, it is essential to strengthen DSD model implementation, access, and utilisation, particularly at the community level.