Initially, Bentonite (Na+) clay was organically-modified by using the cationic surfactant cetyltrimethylammonium bromide (CTAB) to increase the compatibility and interlayered spacing of the clay. After this modification, CTAB modified clay was used for surface grafting with 3-(Trimethoxysilyl) propyl methacrylate silane coupling agent and elemental sulfur by radical polymerization and sol-gel reaction . The nanocomposites were fully characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TGA). The XRD and FTIR confirmed the increase in basal plane spacing and intercalation of surfactant, sulfur and siloxane molecules into the clay gallery. TGA results showed that TMSPM-sulfur grafted MMT exhibits three steps weight loss. The weight loss below 100 oC is from desorption of solvent and moisture molecules and the weight loss occurring after 400 oC is from combustion of the silylated TMSPM.