Abstract Mg–Zn–Ca bulk metallic glass with different compositions (Mg66Zn30Ca4 and Mg70Zn25Ca5) have been prepared for this study and their feasibility as biodegradable metallic materials have been evaluated by the microstructural, surface analysis, mechanical testing, corrosion and cytotoxicity tests. It was found that the Mg66Zn30Ca4 sample presents a more uniform corrosion morphology than as-rolled pure Mg and Mg70Zn25Ca5 samples, with much smaller micro-scale uniformly distributed pores beneath the corrosion product layer. The corrosion products were identified to be Mg(OH)2 and Zn(OH)2 , and a uniform corrosion mechanism is proposed. Both indirect cytotoxicity and direct cell culture experiments were carried out using L929 and MG63 cell lines. The results show higher cell viabilities for Mg–Zn–Ca extracts than that for as-rolled pure Mg. In addition, L929 and MG63 cells were found to adhere and proliferate on the surface of Mg66Zn30Ca4 sample.