Abstract: Friction tests were conducted on the pin-disk friction pair that was composed of cast Q235B steel for magnetic rail brake pole shoes and oil quenched hardened 45 steel. Effects of sliding speed (10-100 km·h^-1), normal load (10-80 N) and lubrication condition (dry friction, water lubrication) on the friction coefficient and wear mechanism were studied. The results show that with increasing sliding speed, the friction coefficient of the friction pair became stable within 3 s. The stable friction coefficients increased first and then decreased with increasing sliding speed. But the variation range of the friction coefficients was small, which was in 0.40-0.55. The normal load had little effect on the friction coefficient. With increasing sliding speed, the wear mechanism of the Q235B steel pin sample changed from abrasive wear to adhesive wear, and increasing normal load led to more serious adhesive wear. Water lubrication during friction could reduce the friction coefficient and the wear degree.