Unlubricated sliding wear tests of Al2O3, Si3N4 and ZrO2 against ductile iron and grey cast iron were carried out on a ring-block wear tester at room temperature. It was found that the wear volume of ceramics increased in the order Al2O3, ZrO2, Si3N4. The wear volume of grey iron was greater than that of ductile iron. Energy-dispersive X-ray analyses of worn surfaces of the ceramics indicated that a large amount of cast iron formed a transfer layer on Al2O3, making the wear volume of Al2O3 the smallest among the three ceramics. The graphite in the cast irons can decrease the wear of the ceramic-cast iron pairs.