Pure magnesium, free from toxic elements, has been identified as a promising candidate for bioabsorbable orthopaedic devices. However, its rapid corrosion in physiological environments presents a significant challenge for practical applications. Chemical coatings, such as polydopamine (PDA), offer a potential solution to improve the corrosion resistance of pure magnesium. Nevertheless, the reaction conditions must be meticulously optimized, particularly in the presence of salts, as magnesium is highly sensitive to environmental factors. In this study, a PDA coating, widely investigated for improving the corrosion resistance of magnesium alloys, was applied to pure magnesium, avoiding the conventional Tris-HCl buffer. Instead, a 0.01 mol/L NaOH aqueous solution was used successfully to coat PDA layer on the surface of pure magnesium. The corrosion behaviour of PDA-coated magnesium was evaluated using electrochemical measurements and magnesium ion elution profiles in a tissue culture medium containing 5 vol% of fetal bovine serum at 37ºC. The results demonstrated that the PDA coating effectively mitigated early-stage corrosion of the pure magnesium substrate. This method provides a straightforward approach to enhancing the corrosion resistance of pure magnesium, and the PDA layer can also function as an intermediate platform for further biofunctional surface modifications, potentially expanding its applications in biomedical fields.