In this study, the effects of Mg addition on the organization refinement and mechanical properties of the alloys were investigated by designing Zn-Mg binary alloys with different compositions. Solution treatment and cold drawing successfully prepared fine wire materials with smooth surface and uniform organization. The material’s mechanical properties were further improved by treating the fine wires with an optimized annealing process. Electrochemical tests and in vitro degradation experiments showed that the degradation properties of the alloy in simulated body fluids were closely related to the alloy composition and microstructure. Cytotoxicity tests showed that the prepared Zn-Mg alloys were significantly cytotoxic to tumor cells. The corrosion weight loss analysis revealed the corrosion behavior of the alloy and its trend with time. Overall, this study provides critical experimental data and theoretical basis for preparing biodegradable biomedical metal-zinc alloys with excellent performance, and lays a solid foundation for future clinical applications.