A novel block mercaptosilane (3-benzothiazolthio-1-propyltriethoxylsilane) (Silane-M) was synthesized and characterized by Fourier transform infrared spectra, H-1 nuclear magnetic resonance, and elemental analysis. Styrene-butadiene rubber (SBR)/silica composites were prepared with Silane-M, and its effect on the properties of materials was Studied. Results show that Silane-M cart substantially improve the dispersion of silica and strengthen the reinforcement of silica for SBR vulcanizates like anchors of silica to rubber matrix. As expected, it enhances the tensile, tear strength, dynamic compression property, and resistance to abrasion of SBR/silica composites. By adding Silane-M into the system, SBR/silica composites get superior skid resistance and high glass transition temperature. (T-g) (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 1967-1973, 2009