[en] This research investigates the dielectric properties (impedance, dielectric constant and dielecteic loss) of SiO2/Ep:TiO2/Ep nanocomposite over the frequency range of (102-106 Hz) at room temperature. The dielectric material used is epoxy resin, while nano-sized titanium dioxide (TiO2) with grain (30 nm), oxide silicon (SiO2) with grain size (12 nm) in state volume ratio 0,0.05,0.1). The effect of gamma by using (CS137) for period time (17) day was studied Radiation caused decreasing in real and imaginary parts of dielectric constant and impedance.