Nanocomposite based on BR/EPDM (50/50) containing organo-modified Nanocaly (closite 15 A) (3, 5, 7 & 10 Wt %) were prepared by two-roll mill. The effect of organo-modified nanosilicate layers on microstructure, morphological and rheological properties of samples were investigated. Results suggested intercalation of polymer chains in to silicate layers and enlarging the d-spacing which was evidenced by X-ray diffraction. According to transmission electron microscopy (TEM) micrographs, the prepared samples have obtained a structure composed of both intercalated and exfoliates layers. Rheological results showed an increase in complex viscosity and elastic modulus for nanoclay filled samples which can attributed to the good interaction between polymer/nanoclay. This good interaction was viewed by SEM photomicrographs of cryogenically fractured surface of the samples.