Abstract: The wear characteristics of diamond and CBN grit are studied using single grit test with carbon steel plate wheel as dressing tools.The results show that the relative velocity of grinding wheel to dressing wheel has an important effect on wear of diamond grits.The abrasive wear reaches 50.1 μm when the relative velocity is 51.9 m/s,and decreases to 19.5 μm as the relative velocity is 17.3 m/s.After comparing grit wear characteristics of diamond and CBN,it can be concluded that chemical interaction between diamond grits and dressing wheel occurrs in the process of diamond grits wear,which accelerates the wear of diamond grits.Graphite material is not detected on the dressed grit using Raman spectra analysis.