Abstract: In this paper, glass fiber @PVDF (the volume percentage of glass fiber x is 0, 5%, 10%, 15% and 20%) dielectric composites were prepared by solution blending method.The effect of glass fiber percentage on the dielectric properties of glass-fiber@ PVDF dielectric composites was studied by SEM microscopic morphology analysis and dielectric property test.The test results show that with the increase of the glass fiber percentage, the defects and interfaces of the sample increase, due to the accumulation of space charge and the easier diffusion of charge at the interface, significant interface polarization occurs, the dielectric constant and dielectric loss gradually increase, the breakdown strength gradually decreases, and the energy storage density first increases and then decreases.When the volume percentage of glass fiber is 15%, the sample of G3 obtains the maximum energy storage density, which reaches 2.38J/cm³.