The　orbital　hybridization　between　metal　and　oxygen　of　perovskite　catalysts　can　lower　the　overpotential　and　enhance　the　oxygen　evolution　reaction　(OER)　activity.　This　study　combines　density　functional　theory　with　experiments　to　clarify　how　Sr/Fe　codoping　modulates　orbital　hybridization　and　enhances　OER　catalytic　activity　of　LaCoO3.　The　as-prepared　La0.50Sr0.50Co0.75Fe0.25O3　shows　remarkable　performance　with　a　low　overpotential　of　310　mV　at　10　mA　cm-2　current　density　and　a　107.03　mV　dec-1　Tafel　slope,　outperforming　most　state-of-the-art　perovskite-based　OER　electrocatalysts.　The　experimental　results　confirm　that　Sr/Fe　codoping　enhances　the　expansion　of　Co-O-Co　bond　angles　and　strengthens　the　covalency　of　the　Co-O　bond　in　LaCoO3,　leading　to　enhanced　electrocatalytic　activity.　Moreover,　increasing　Sr　doping　reduces　the　distance　between　the　Co　3d/O　2p　center　and　the　Fermi　level,　decreasing　the　energy　difference　between　them　and　enhancing　the　degree　of　orbital　hybridization　between　Co　3d　and　O　2p.　As　the　degree　of　Co　3d/O　2p　orbital　hybridization　increases,　a　higher　charge　transfer　was　found　between　the　active　center　and　intermediate　product,　OOH,　reducing　the　energy　barrier　of　the　rate-determining　step　while　lowering　the　overpotential.　This　study　provides　thorough　insight　into　the　rational　design　of　OER　catalysts　based　on　orbital　hybridization.　©　2024　American　Chemical　Society.