The discovery and use of antibiotics provide us a powerful weapon against bacterial infection. However, the long-term use of antibiotics leads to bacterial resistance and limits their clinical applications. Fortunately, the rapid development of nanotechnology provides new ways to solve the problem. In this review, nano-enzymes were classified into two types:one is "the composites of enzyme and nanomaterial", another is "the nanomaterials possessing enzyme-mimic activities-named as nanozymes". To the best of our knowledge, Ag nanoparticles have been widely studied as nano-antibacterial agents and their antibacterial mechanisms are diverse. Therefore, the antibacterial mechanism and the latest progress of Ag nanoparticles as nano antibacterial agents are discussed. Compared to natural enzymes, the nanozyme-based antibacterial agent can integrate more than one strategy to yield synergistic effects and thus increase their bacterial killing efficacies. Therefore, in this review, we focus on recent progress in the design and mechanism of nanozyme-based antibacterial agents including the Ag nanoparticles, composites of enzymes and nanomaterials and nanoparticles possess enzyme mimic activities (nanozymes). Finally, the current challenges and an outlook for the development of more effective and safer antibacterial nano-enzymes are also included.