In order to investigate the wear characteristics of pantograph slide in pantogragh-catenary under different current,contact pressure and sliding speed,current-carrying wear experiments were carried out to study the current-carrying efficiency,arc energy,friction coefficient and temperature of the friction pair under different working conditions.The wear area of the slide was measured in blocks and multiple times after the experiments,and the surface topography images and roughness parameters of the slides were collected by metallographic microscope and surface roughness instrument respectively.An image processing method based on Otsu algorithm was used to extract pits from the topography images and perform mark calculation,and the variation of the area and number of pits,and the roughness parameters(contour arithmetic mean deviation and maximum contour valley depth) under different working conditions was statistically analyzed.The results show that with the increase of current,the area and number of pits increase,and the roughness parameters decrease.With the increase of contact pressure,the area of pits decreases,the number of pits decreases first and then increases slightly,and the roughness parameters decrease.With the increase of sliding speed,the area and number of pits and the roughness parameters increase.