The ethylene-propylene-diene monomer/styrene-butadiene rubber (EPDM/SBR)-nanosilica (SiO2) nanocomposite was prepared. The 0-10 parts per hundred rubber (phr) of SiO2 with EPDM/SBR was mixed on a two-roll mill. The effect of nanosilica (0-10 phr), and silane coupling agent (bis(triethoxysilylpropyl)-tetrasulphide) (TESPT) on the curing characteristics, mechanical properties, rebound resilience, compression characteristics, abrasion, swelling property and morphological characteristics of the EPDM/SBR-SiO2 nanocomposites was investigated and studied. From the results, it was clear that the mechanical, wear and swelling properties steps-up with increase in the content of nanosilica particles in it. The addition of TESPT enhances the properties of the nanocomposites to a greater extent. From the analysis, it was clear that the effect of nanosilica concentration in the rubber composite with TESPT was found to be superior compared to nanocomposites without it.