Nanocomposite solid polymer electrolytes (NSPEs) based on poly (vinylidene fluoride) (PVDF) were prepared by dispersing organically modified clay (Cloisite®30B, C30B) consisted of silicate layers in the polymer matrix. And ion conductive properties were investigated in relation to dispersed condition of silicate layers and structural changes of nanocomposites. The characterizations of PVDF/C30B nanocomposites with various C30B contents were analyzed by XRD, DSC, DMA and SEM. In order to confirm the ion conductive properties of NSPEs added to lithium trifluoromethansulfonate (LiCF3SO3) at room temperature, ac impedance analyzer and FT-IR spectrometer were used in this study. The degree of C30B dispersion in PVDF and the degree of crystallinity of PVDF/C30B nanocomposites showed the decrease with C30B contents. As a result, high ionic conductivity was observed in the sample added to 3wt% clay in the polymer matrix and the maximum conductivity was 9x10-4S/cm.