Bacterial infections pose a significant threat to human health and a heavy burden on the global healthcare system. Antibiotics are the primary treatment, but they can lead to bacterial resistance and adverse side effects. Two-dimensional (2D) nanomaterials such as graphene, MoS2, and MXene have emerged as novel antibacterial agents due to their potential to circumvent bacterial resistance. Among the 2D nanomaterials, black phosphorus nanosheets (BPNs) have attracted great research interest due to their excellent biocompatibility. BPNs possess unique properties, such as a high specific surface area, tunable bandgap, and easy surface functionalization, enabling them to combat bacteria through physical disruption of bacterial membranes, photothermal and photodynamic therapies. However, the low preparation efficiency and inevitable oxidative degradation of BPNs have limited their wide application. This review provides a comprehensive overview of recent advances in antibacterial research on BPNs, encompassing their preparation methods, structural and physicochemical properties, antibacterial mechanisms, and potential applications. By addressing the challenges and prospects of using BPNs as an alternative to antibiotics, this review provides valuable insights and guidance for utilizing BPNs in shaping the future of antibacterial therapy.