Theoretically,　triggering　the　lattice　oxygen　mechanism　(LOM)　of　the　catalysts　during　the　alkaline　oxygen　evolution　reaction　(OER)　can　effectively　break　through　the　thermodynamic　limitations,　while　following　this　path,　the　rate　of　simultaneous　deprotonation　also　determines　the　overall　kinetics.　A　cerium　oxide　units‐modified　cobalt　(oxy)hydroxide　nanocomposite　of　CeO2‐CoOOH/NF　is　proposed,　where　the　Ce(4f)‐O(2p)‐Co　(3d)　coupling　with　sites　interaction　mediates　the　Co─O　Mott–Hubbard　splitting　state　to　trigger　efficient　LOM.　Meanwhile,　the　4f　orbital　electron‐rich　state　near　the　Fermi　level　is　favorable　for　proceeding　the　electron‐involved　deprotonation　behavior.　All　these　empower　CeO2‐CoOOH/NF　with　considerable　OER　activity,　which　delivers　an　overpotential　of　249 mV　at　10 mA cm−2,　and　coupling　with　commercial　Pt/C　in　anion　exchange　membrane　water　electrolyze　(AEMWE)　to　realize　energy‐saving　hydrogen　production.　This　work　is　instructive　for　the　design　of　high‐performance　OER　catalysts　through　controlling　the　electron　orbitals　hybridization　state　of　the　catalysts　to　synchronously　accelerate　the　kinetics　of　each　link　in　OER.