Dual　metal-organic　frameworks　(MOFs,　i.e.,　MIL-100(Fe)　and　ZIF-8)　are　thermally　converted　into　Fe-Fe3C-embedded　Fe-N-codoped　carbon　as　platinum　group　metal　(PGM)-free　oxygen　reduction　reaction　(ORR)　electrocatalysts.　Pyrolysis　enables　imidazolate　in　ZIF-8　rearranged　into　highly　N-doped　carbon,　while　Fe　from　MIL-100(Fe)　into　N-ligated　atomic　sites　concurrently　with　a　few　Fe-Fe3C　nanoparticles.　Upon　precise　control　of　MOF　compositions,　the　optimal　catalyst　is　highly　active　for　the　ORR　in　half-cells　(0.88　V　in　base　and　0.79　V　versus　RHE　in　acid　in　half-wave　potential),　a　proton　exchange　membrane　fuel　cell　(0.76　W　cm(-2)　in　peak　power　density)　and　an　aprotic　Li-O-2　battery　(8749　mAh　g(-1)　in　discharge　capacity),　representing　a　state-of-the-art　PGM-free　ORR　catalyst.　In　the　material,　amorphous　carbon　with　partial　graphitization　ensures　high　active　site　exposure　and　fast　charge　transfer　simultaneously.　Macropores　facilitate　mass　transport　to　the　catalyst　surface,　followed　by　oxygen　penetration　in　micropores　to　reach　the　infiltrated　active　sites.　Further　modeling　simulations　shed　light　on　the　true　Fe-Fe3C　contribution　to　the　catalyst　performance,　suggesting　Fe3C　enhances　oxygen　affinity,　while　metallic　Fe　promotes　*OH　desorption　as　the　rate-determining　step　at　the　nearby　Fe-N-C　sites.　These　findings　demonstrate　MOFs　as　model　system　for　rational　design　of　electrocatalyst　for　energy-based　functional　applications.