Abstract: As an important surface strengthening technology, micro-arc ion deposition has features such as high metallurgical bonding strength, small heat-affected zone, parts being not easy to deform, and wide range of application. It is widely used in the fields of cutting tools, molds, energy, agriculture, and aerospace, and it can realize the purpose of improving abrasion and corrosion resistance, flame retardant properties on the surface of the parts, and repairing surface damage of the parts. This paper introduces principle of micro-arc ion deposition technology and its characteristics, and introduces research status of micro-arc ion deposition equipment from three aspects, that is improvement of pulse power supply, improvement of electrode movement form and research of automatic deposition. The application of micro-arc ion deposition technology is introduced from four aspects, that is wear resistance, corrosion resistance, flame retardant and surface repair. Finally, problems of micro-arc ion deposition technology are summarised, and its future development direction is foreseen.