Iron-nitrogen-carbon　(Fe-N-C)　catalyst　has　emerged　as　highly　promising　contender　for　oxygen　reduction　reaction　(ORR),　yet　challenges　such　as　limited　active　site　accessibility　and　intricate　synthesis　procedures　impede　their　commercialization　as　a　replacement　for　the　benchmark　Pt/C　catalyst.　Herein,　we　present　an　innovative　approach　to　in　situ　fabricate　a　unique　iron　and　nitrogen　co-doped　3D　porous　carbon　material.　The　material　is　synthesized　through　a　straightforward　one-step　pyrolysis　of　xanthine,　oxidized　carbon　nanotubes　and　iron　nitrate　nonahydrate　mixture.　During　the　high　temperature　pyrolysis,　the　nucleobase　xanthine　undergoes　gradually　transformation　into　an　efficient　N-doped　graphene-like　material.　Simultaneously,　it　assembles　with　carbon　nanotubes　(CNTs),　resulting　in　the　formation　of　a　unique　3D　graphene-CNTs　composite　structure　composed　of　graphene　and　CNTs.　This　exceptional　3D　porous　structure　serves　as　an　excellent　scaffold,　ensuring　firm　anchoring,　uniform　dispersion,　and　optimal　exposure　of　numerous　FeNx　active　sites.　Leveraging　this　well-engineered　framework,　the　optimized　Fe-N-C　catalyst　(NC/CNT/Fe0.04)　shows　excellent　ORR　performance　with　an　onset　potential　of　1.03　V　vs.　RHE,　a　half-wave　potential　of　0.87　V　vs.　RHE,　and　a　diffusion-limited　current　density　of　−5.59　mA　cm−2,　even　better　than　those　of　the　commercial　Pt/C　catalyst.　This　work　provides　valuable　insights　into　the　design　of　efficient　electrocatalysts　with　3D　channel.　©　2024　Elsevier　Ltd