In this research, the activity of Fe-Co/KB (ketjenblack carbon) has been studied as a cathode catalyst for oxygen reduction reaction (ORR) in phosphate buffer saline (PBS) in presence of a solution containing low concentrations of glucose and amino acids mixture (near to physiological tissue fluid in the human body). It is worthwhile to mention that Fe-Co/KB cathode catalyst with size of 3 nm, determined by TEM, indicated an exceptional selectivity towards ORR. Results also revealed that Fe-Co/KB has a higher activity compare to 80%wt Pt/C in ORR with a superior tolerance towards poisoning agents. Further electrochemical investigations were carried out in a two-chamber implantable glucose fuel cell (IGFC) utilizing Fe-Co/KB in the cathode side. Time-dependent evaluation of cell voltage at constant current discharge 0.02 mAcm(-2) in PBS (pH = 7.4) solution containing 5 mM glucose showed only 16% loss in cathode potential; demonstrating an acceptable performance of cathode catalyst in IGFC. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.