An efficient method was developed to produce highly dispersed Pd nano particles (NPs), supported on Nafion-graphene film by electrochemical deposition at constant potential in presence of ferrous ions. The Fe2+ ions govern the size, shape and morphology of Pd NPs. The as-prepared catalyst was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). It was obeserved from TEM that the mean diameter of electrodeposited Pd NPs was 6.4 ± 1.3 nm with narrow diameter range from 4 to 10 nm. The electrocatalytic performance of the Pd NPs deposited on Nafion-graphene (Nf-G) catalyst was studied by cyclic voltametry (CV) and chronoamperometric measurements. The highly dispersed Pd NPs on Nf-G film were obtained in presence of Fe2+ ions. This alters electrochemical active surface area and hence catalytic activity of Pd NPs. The prepared Pd/Nf-G catalyst exhibit highest tolerance to the intermediate poisoning species (ratio If/Ib = 2.2). The as-obtained catalyst shows an efficient electrocatalytic activity and good stability for ethanol oxidation in alkaline medium.