in the present work Graphene nanoplatelets (GNPs) and carbon nanotubes (CNTs) were chemically functionalized and incorporated into miscible polyvinylidene fluoride (PVDF)/ Poly(methyl methacrylate) (PMMA) blends through solution mixing to obtain high β polymorphic (pizoelectric) structure of PVDF nanocomposites. The frequency sweep test results showed greater enhancement in storage modulus (G′) at low frequency range for fCNT filled nanocomposite compared to fGNP filled nanocomposite. this indicating a stronger physical network formed in fCNT filled sample. The electrical and rheological percolation thresholds of the CNT filled nanocomposites was found to be 1wt% and 1.2wt% loading, respectively, However the percolation threshold could hardly be obtained for GNP filled nanocomposite up to 4 wt % loadings. This result were found to be in consistent with the results of electrical conductivity measurements. From DSC results it was found that fCNT had greater enhancement effect on crystallinity of PVDF than that of fGNP, A similar trend was observed for nucleation efficiency and isothermal crystallization of PVDF for these two nanoparticle. The XRD and FTIR results showed that the addition of fCNT or fGNP both had an increasing effect on β polymorphic crystalline structure formation with greater exchange for fCNT these was attributed to more specific interaction between C=O functional groups in CNT and CF2 groups of PVDF. The present study will practically be significant to further extend the application of PVDF composite.