Polyamide 6 (PA6) / Poly Phenylene Oxide (PPO) / carbon nanotube (CNT) / conductive carbon black (CCB) nanocomposites with incorporation of PPO grafted with Maleic anhydride (PPO-g-MA) were prepared via melt blending method to examine the effect of PPO-g-MA on electrical conductivity of the nanocomposite. Investigation of PPO-g-MA was performed by Fourier transform infrared (FTIR) and Titration to determine the presence and content of MA in PPO-g-MA. Morphological, electrical and mechanical properties of PA6/PPO/CNT/CCB (with and without PPO-g-MA) nanocomposites were examined by field emission scanning electron microscopy (FESEM), digital insulation tester, tensile test and impact test. The results showed that by incorporation of PPO-g-MA (5 wt.%) to a compound containing 2.5 wt.% CNT and 5 wt.% CCB, electrical conductivity was improved about 1.5 orders of magnitude (S cm-1) compared to those samples without any PPO-g-MA. Electrical conductivity enhancement was observed in both low viscosity and high viscosity PA6 matrix. It was concluded that the electrical conductivity enhancement is due to the reduction of the PPO droplet size (about 50 %) in PA6 matrix as a result of employing the PPO-g-MA. These results illustrate that the PPO-g-MA has a considerable effect on electrical conductivity in addition to the effect on mechanical properties, which is generally the main reason for employing Polymer-g-MA in different blends. The novelty of the present study lies in the consideration of the electrical conductivity enhancement along with mechanical properties improvement of a widely used nanocomposites by using PPO-g-MA.