Kaolin unmodified and modified with the following silanes: 3-aminopropyltriethoxysilane, N-2- aminoethyl-3-aminopropyltriethoxysilane and 3-metacryloxypropyltrimethoxysilane has been character- ised as to its physico-chemical properties (DTA and SEM methods) and mechanical performance. The course of vulcanisation of rubber blends and physical properties of butadiene–styrene rubber (KER 1500) vulcanisates containing unmodified and modified kaolin have been determined. The vulcanisates filled with kaolin modified with silane compounds containing amine groups have been found to show better mechanical performance than those with kaolin modified with 3 metacryloxypropyltrimethoxysilane and unmodified kaolin.