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Mesoporous silica is used as filler for styrene–butadiene rubber (SBR); filler–polymer interactions are compared with those exhibited when commercial ultrasil silica (VN3) is used. A silane coupling agent is added to improve the filler dispersion and its influence on the bound rubber formation is also investigated before vulcanization. The bound rubber content is higher for the mesoporous silica and increases further for the sample containing alquil silanes improving the mechanical properties. For vulcanized samples, the reinforcing is measured by the vulcanization degree and the mechanical properties. The swelling degree, elastic modulus and glass transition temperature (Tg) are higher for samples containing mesoporous silica and increased by the use of organosilane (bis- trietoxisililpropil tetrasulfano (TESPT) or bis-trietoxisililpropil disulfano (TESPD) during vulcanization. The vulcanization kinetics of the SBR is evaluated by rheometry and differential scanning calorimetry. The vulcanization rate is higher for the rubber filled with mesoporous silica indicating its autocatalytic effect. This can be explained by chemical interactions between the filler and rubber and the penetration of the rubber chains into the mesopore.