The piezoelectric properties of PVDF mainly depend on its β phase. In this paper, we investigated through piezoresponse force microscopy the piezoelectric properties of PVDF composite films when we induce the formation of β-phase crystals adding a nanofiller, like graphene nanoplatelets or zinc-oxide nanorods, but without applying any electrical poling. At first, we fabricated piezoelectric PVDF nanocomposite films by the solution casting method. Then, we investigated the piezoelectric response of the different samples produced and we investigated the correlation between piezoresponse, morphology and structural characteristics of the nanocomposite. The morphology of the produced samples was investigated through field-emission scanning electron microscopy and atomic force microscopy. The β-phase formation was assessed through Fourier transform infrared spectroscopy measurements.