In this article, a chemical kinetics mechanism was proposed for the chemical mechanical polishing (CMP) system of mixed-abrasive slurry. Under the consideration of a pad as a sort of catalyst, a polishing rate equation was deduced. Compared to the previous equations, the present equation is in terms of the abrasive concentration. With the limited experimental data, the present equation may work for describing the CMP mechanism. (c) 2004 Elsevier B.V. All rights reserved.