Dielectric materials with high dielectric permittivity and low dielectric loss are desirable in preparing dielectric devices. In this work, polypropylene (PP) grafted maleic anhydride (PP-g) was introduced both in improving the compatibility of PP/poly (vinylidene fluoride) (PVDF) blends and dispersing the incorporated nanoparticles in PP/PVDF blends. When 40 wt% BaTiO3 and 0.75 wt% graphene were loaded, the tensile strength is increased by 31% and the tensile modulus is twice of the PP/PVDF blends without addition of PP-g. Moreover, the polymer composites also exhibit improved dielectric permittivity and loss tangent. The exact value is 11 and 0.08 at 10(3) Hz with 40 wt% BaTiO3 and 0.5 wt% Graphene, or 16 and 0.11 with 40 wt% BaTiO3 and 0.75 wt% Graphene. The selective distribution of BaTiO3 in PP phase and location of Graphene between the interfacial of PP and PVDF ensured the improved mechanical properties and dielectric permittivity without inducing large increase in loss tangent, which provides a way in incorporating inorganic fillers into polymer blends with unique distribution morphology to fabricate high performance dielectric materials.