Abstract: The parameters m and k in grinding kinetics equation were studied by using analytic geometry and partial derivativ method. The analyses include not only the relationship between the parameters and the grinding time， but also the effect on the grinding speed. It turned out that the parameter k mainly affects oversized cumulative productivity R when te1/k. The larger parameter k is，the faster grinding speed is. With the increase of the grinding time the parameter m mainly affects oversized cumulative productivity R when te1/k. The larger parameter m is， the faster grinding speed is. Moreover， the conclusion was verified according to previous studies. The above theoretical results can fully explain the grinding speed under the different grinding conditions and material properties.

Key words: parameters of grinding kinetics, grinding time, grinding kinetics equation, partial derivative