In this study, the doping metal oxides; ZnO and Al2O3, (MO for short) into poly (aniline) (PANI) how that affects the dielectric properties have been investigated by the impedance analysis technique. PANI, PANI-Al2O3 and PANI-ZnO were synthesized by chemical oxidative polymerization. Both FTIR and SEM are used to characterize the structure and morphologies of these composites. Dielectric properties of PANI and PANI–MO composites have been performed in the frequency range 100 Hz −1 MHz. It was seen that the values of the dielectric constant and impedance increase with doping Al2O3and ZnO into PANI. Absorption coefficient (α) and relaxation times (τ) parameters were calculated and it is revealed that the relaxation mechanism changed significantly by the doping of metal oxide into PANI. Moreover, the conductivity properties of PANI-MO composites were performed and it is seen that “s” parameter value correlated Barrier Hoping (CBH) Mechanism.