The purpose of this study is to determine the grindability and kinetic behavior of clinker and colemanite in cement production when they are ground separately and together. Bond and Hardgrove grindability methods were employed to determine grindability properties clinker and colemanite by varying proportions. Bond work index (BWI) values of clinker and colemanite are 18.89kWh/t and 12.33kWh/t, respectively. BWI value of mixture decreases by added colemanite and the experimental BWI values of mixtures were lower than those of calculated, considering their proportions. Hardgrove grindability index (HGI) values of clinker and colemanite are 51.81 and 99.62, and Blaine fineness values are 920cm(2)/g and 2430cm(2)/g, respectively. As colemanite addition increases HGI and Blaine fineness values also increase. Experimental Blaine fineness values are greater than calculated values meaning that during intergrinding different ingredients do not show the same behavior as in the case of separate grinding. These findings explain that clinker particles have an abrasion effect thus an extra grinding effect on colemanite particles. The specific rates of breakage were determined through kinetic experiments to understand the grinding mechanisms of colemanite, clinker and their mixtures. The model parameters of S-i, a(T), and were established in kinetic experiments.