Elastomer nanocomposites based on natural rubber (NR), butadiene rubber (BR), and styrene butadiene rubber (SBR) containing Cloisite 15A were prepared using a two-roll mill. Mechanical, morphological, and rheological characterization of the prepared nanocomposites was carried out in order to study the effect of different nanoclay compositions, i.e., 1, 3, 5, 7, and 10 wt %. Intercalation of the elastomer chains into the silicate layers was evidenced by d-spacing values calculated according to the results of the X-ray diffraction (XRD) patterns. This was directly confirmed by transmission and scanning electron microscopy (TEM and SEM). The results depict a decreasing trend in the optimum cure time (t 90 ) and scorch time (t 5 ) values of the nanocomposite samples with increasing nanoclay loading; where the elastic modulus (G 0 ) and complex viscosity (g*) of the samples considerably increased. The mechanical properties of the nanocomposites show a considerable increase in the tensile modulus of NR/BR/SBR/Cloisite 15A nanocomposites.