In this study, Poly (vinyl alcohol) - Poly (ethylene glycol) (PVA-PEG) poly-blend and its composite with 5wt.% and different wt.% (2, 4, and 6) of Co3O4 films were synthesized using blend casting method. The characterization was considered such as; Fourier transforms infrared (FT-IR), electrical properties, and its application for gamma ray shielding. The electrical properties showed that the dielectric constant and dielectric loss for all different rates of Co3O4 particles decreases with the increase of the electric field frequency, and that its values increase with the increasing of the wt.% of Co3O4 particles. The (PVA-PEG) poly-blend and its composite with and different wt.% of Co3O4 films have good linear attenuation coefficients for gamma ray radiation.