Abstract: Effect of trace Cr addition on wear property of four Cu-Ag-Cr alloys and wear mechanism were studied under an electrical current by means of electrical sliding wear tests, scanning electron microscopy (SEM), energy dispersive X-ray spectrum (EDS) and transmission electron microscopy. Results showed that wear rate of Cu-Ag alloy further decreased with increase of the Cr content. However, wear rate of all of materials increased with increase of the sliding distance and electrical current. Compared with Cu-Ag alloy under the same conditions, Cu-Ag-Cr alloy wire had much better wear resistance, which was caused by dispersed fine precipitates due to trace Cr addition. Adhesive wear, abrasive wear and electrical erosion were the dominant mechanisms during the electrical sliding processes.