The possibility of employing chalk from the Kornica deposit as a filler for butadiene-styrene rubber has been studied. Basic chemical and physico-chemical analyses of the chalk were performed. In order to upgrade the purity and physico-chemical parameters, the chalk was subjected to washing in a three-drum washmill equipped with a screen and to a three-stage granulometric classification. Chalk samples were modified with various proadhesion compounds and triisostearoyl isopropyl titanate was found to be the most efficient modifier. The chalk modified with triisostearoyl isopropyl titanate resulted in the highest strength parameters of rubber vulcanizates.