The wear mechanism of several kinds of diamond circular saw blades was studied in the different sawing parameters during dry cutting of cement concrete, ferroconcrete and steel fiber reinforced concrete. Seven wear forms of diamond grits were obtained in the sawing experiments. The cobalt based bond shown the best wear resistance. It showed that the damage of blade body was caused by thermal damage and the scratching action of concrete chips. The result indicates that the wear of diamond saw blades arises mostly from the difficult chips removing, high cutting temperature and drastic impacting in dry sawing.