Core-Shell structures of Ag@Pt Nanoparticles (NPs) dispersed on different carbon base supports such as Graphene Oxide (GO), Multiwall Carbon Nanotubes (MWCNT) and Carbon black (CB) Vulcan applied to the oxygen reduction reaction (ORR) in a Proton Exchange Membrane Fuel Cell (PEMFC). Electrocatalysts synthesized through the ultrasonic treatment method. The morphology of as prepared materials characterized through the High Resolution Transmission Electron Microscopy (HRTEM) and X-ray diffraction (XRD) analyses. The ORR activities and stabilities of electrocatalysts studied through electrochemical measurements of Cyclic Voltammetry (CV) and single cell tests, respectively. Results revealed all prepared carbon based electrocatalysts displayed Core-Shell nanostructures moreover; the Ag@Pt/rGO with Ag:Pt mass ratio of 1:3 possessed the largest electrochemical surface area of 77.6 m2/g amongst all synthesized materials. The maximum power density of the membrane electrode assembly (MEA) prepared with Ag@Pt/rGO determined to be 55% higher than that of the commercial Pt/C species. In addition, this was considerably higher than corresponding values of other mentioned synthesized electrocatalysts in this research. These results evaluated through single cell techniques. The understudied core-shell material based upon the rGO considered as a very promising cathode for utilizing in PEMFCs.