Good biosafety, biocompatibility and valuable self-degradation properties endow medical magnesium and magnesium alloys with great potential to replace inert implant materials in the field of traditional clinical applications. The excessive degradation rate of magnesium alloy, however, leads to its premature loss of structural integrity and mechanical support, being unable to complete the effective service time necessary for tissue healing of the implant site. At the same time, it is also its excessive degradation rate that leads to the intensification of hydrogen evolution reaction of magnesium alloy. Because it cannot be absorbed by the human body in a short time, the excessive H2 will easily gather around the implant or form a subcutaneous airbag, which will not only cause the inflammation of the implant site, but also hinder the adhesion and growth of cells in the implant, limiting its clinical application prospects. Surface modification technology can effectively delay the degradation rate of medical magnesium and magnesium alloys, and reduce the rate of hydrogen evolution.