The main question about using silver nanoparticle coating as an antibacterial agent in implant systems to reduce the incidence of biomaterial-associated infections has been the risk of toxicity to the human cells which is linked to the release behavior. In this work, it has been illustrated that the controlled release behavior with a minimal amount of Ag ions can be achieved via simple straightforward electrochemical anodization of Zr-Ag alloy (the wt% of Ag kept at ~ 1 wt%). The antibacterial test showed an effective antibacterial activity against the Gram-positive and Gram-negative model bacteria S. aureus and E. coli and for the first time to the best of our knowledge, it was shown that ZrNT possesses antibacterial properties against Gram-negative bacteria. In future work, the antimicrobial activity of the 2 tested substrates should be screened for more bacterial species to prove if these antibacterial effects can be generalized for Gram-positive and Gram-negative bacteria. Additionally, the influence of the nanostructural morphology on the antibacterial activity, as well as the impact of Ag decoration on the integration with human tissues should investigated more in-depth.