Orthodontic micro-implants, as an absolute anchorage, has the advantages of smaller trauma, better stability, higher comfort, as well as less dependence on the patients, which promotes its rapid development. This paper introduced the current situation and research progress in clinical application of micro-implants anchorage in orthodontic treatment for children and the concept of safe zone. At last, the parameters that affect the success rate and initial stability had been analyzed, aiming to comb the lines of thinking and methods for the researches on micro implant anchorage in orthodontics and provide reference for its further research and clinical application.