Abstract: Antibacterial activity and mechanical properties of FeCoCr-Ag medium entropy alloys were studied via combinatorial fabrication paired with high-throughput characterizations. It was found that the antibacterial activity and mechanical properties exhibit non-linear dependence on the content of Ag addition. Within the studied alloys, (FeCoCr)₈₀Ag₂₀ possesses an optimized combination of different properties for potential applications as antibacterial coating materials. The underlying mechanism is ascribed to the formation of a dual-phase structure that leads to competition between the role of Ag phase and FeCoCr phase at different Ag content. The results not only demonstrate the power and effectiveness of combinatorial methods in multi-parameter optimization but also indicate the potential of high entropy alloys as antibacterial materials.