Abstract: Due to its efficiency,precision and convenience,CAD/CAM system will be used more and more widely in the prosthodontics to restore the function,shape and beauty of the teeth. And the all-ceramic materials are important to popularize the CAD/CAM system. In this paper,the abrasive characteristics of all-ceramic materials were studied by using MM200 wear testing machine with 80 mesh sands as the abrasion medium. The weight losses of ceramic samples after abrasive testing of certain time were measured and surfaces were then observed under SEM. The results show that the biggest weight loss and obvious crack are found for lithium disilicate glass ceramic because of the high brittleness. Presintering ceramics have less weight losses and smoother surfaces comparing to feldspar ceramics.