A family of cheap carbon black based Fe-Nx/C electrocatalysts with superhigh-performance for oxygen reduction reaction (ORR) were synthesized. The one with Fe 10 wt% and N 1.57 wt% shows the best performance. The activity order of different active sites for ORR was revealed firstly: Fe-N4/2-C > Fe4-N-C > N-C ≫ Fe4-C ≈ C.