Objective To review the progress of in vivo study on degradable magnesium alloys application as bone-implant materials. Methods Recent literature was extensively reviewed and summarized, concerning the in vivo study on degradable magnesium alloys as orthopaedic implants. Results Magnesium alloys possess a natural ability to degrade via corrosion in vivo, which is promising candidate material for orthopaedic medical device applications. A great progress has been made to improve in vivo performance and integration with bone tissue. However, the degradation mechanism of magnesium-based materials in the physiological environment and long-term effect on body are not available. The modulation of the corrosion rate of magnesium alloys must also be accomplished. Conclusion Magnesium alloys have the potential to serve as degradable implants for orthopaedic applications, but a great deal of further investigation is still necessary.