Integral droppers are the core equipment for the catenary current-carrying system. A substantial deterioration in operating conditions (such as the high-frequency vibration, overstressing and current overloading) caused the premature failure of integral droppers with reduced service life. The bending fretting fatigue behaviours and damage mechanisms of the integral dropper from high-speed railway catenary system was investigated. The variation of the mechanical responses, fracture morphologies, chemical compositions in the damage region and corresponding damage mechanisms under the influence of current intensity were discussed in detail. Results showed that the bending fretting fatigue life of the integral dropper decreased with increasing current intensity, the oxidation degree of the fracture and its surface increasingly deepened, and the tensile strength of the wires decreased.