In the drilling process of deep and extra-deep well， the downhole drilling tools are in a situation of high temperature， high pressure and high corrosion， and the drill pipes are intensely collided and worn with the external rock layers and casing. Therefore， the anti-wear and protection of the drilling tools is a problem that needs to be focused on. At present， welding anti-wear belt on drilling tools is the main method of drilling tool protection for deep wells， which plays an important role in reducing drilling tool wear and prolonging drilling tool life. This paper summarizes the development and research status of anti-wear belt technology at home and abroad， expounds the failure causes of anti-wear belt， the evaluation and test methods of key performance. Moreover， the key points of the development of anti-wear belt technology at present are also analyzed， which are anti-shedding， anti-wear belt repair technology and casing-friendly anti-wear belt material research. Finally， the development trend of anti-wear belt technology in deep and extra-deep wells is prospected.