Wear of contact strip on the pantograph of electric railway vehicles is mainly governed by the condition of electric current and contact between contact strip and contact wire. A sliding wear test was carried out under electric current for the combination of Cu-impregnated carbon strip and Cu disk at a sliding speed of 100 km/h. Voltage drop and current were measured at a frequency of 48 kHz throughout the test and occurrence and energy of contact break discharge were evaluated for every revolution of disk. The effect of arc discharge on the wear rate of metallized carbon contact strip was discussed.