Optimizing　the　local　electronic　structure　of　electrocatalysts　can　effectively　lower　the　energy　barrier　of　electrochemical　reactions,　thus　enhancing　the　electrocatalytic　activity.　However,　the　intrinsic　contribution　of　the　electronic　effect　is　still　experimentally　unclear.　In　this　work,　the　electron　injection-incomplete　discharge　approach　to　achieve　the　electron　accumulation　(EA)　degree　on　the　nickel-iron　layered　double　hydroxide　(NiFe　LDH)　is　proposed,　to　reveal　the　intrinsic　contribution　of　EA　toward　oxygen　evolution　reaction　(OER).　Such　NiFe　LDH　with　EA　effect　results　in　only　262　mV　overpotential　to　reach　50　mA　cm-2,　which　is　51　mV-lower　compared　with　pristine　NiFe　LDH　(313　mV),　and　reduced　Tafel　slope　of　54.8　mV　dec-1　than　NiFe　LDH　(107.5　mV　dec-1).　Spectroscopy　characterizations　combined　with　theoretical　calculations　confirm　that　the　EA　near　concomitant　Vo　can　induce　a　narrower　energy　gap　and　lower　thermodynamic　barrier　to　enhance　OER　performance.　This　study　clarifies　the　mechanism　of　the　EA　effect　on　OER　activity,　providing　a　direct　electronic　structure　modulation　guideline　for　effective　electrocatalyst　design.　The　electron　accumulation　(EA)　on　the　NiFe　LDH　can　modulate　the　electronic　structure　directly　to　enhance　the　OER　performance.　Spectroscopy　and　theoretical　calculations　confirm　EA　near　concomitant　Vo　narrows　the　energy　gap　and　reduces　the　thermodynamic　barrier.　This　study　clarifies　the　effect　of　EA　on　OER　activity　and　provides　an　electron　injection-incomplete　discharging　approach　for　effective　electrocatalyst　design.　image