Abstract: Under different current intensity conditions, the evolution of bending fretting fatigue damage of copper-magnesium alloy was studied. The infrared thermograph imager was used to map the temperature distribution of the micro-motion contact zone under current conditions. The surface morphology and chemical behavior of the sample contact damage area were analyzed in detail according to a series of microscopic analysis equipment, scanning, e.g. three-dimensional morphomete, scanning electron microscope, electron microprobe, X-ray photoelectron spectroscopy. Under the same number of cycles, with the increase of current intensity, the bending fretting fatigue life gradually decreased, the temperature of the contact zone gradually increased, the size of the contact damage zone increased, the spalling layer gradually refined, and the degree of oxidation in the contact damage zone increased. The main components of oxidized wear debris were CuO and Cu₂O. The main damage mechanisms were oxidative wear, adhesive wear and spalling.