The　electrolysis　of　water　requires　excess　energy　in　the　form　of　overpotential　to　overcome　activation　barriers　due　to　the　sluggish　kinetics　of　both　the　hydrogen　evolution　reaction　(HER)　and　oxygen　evolution　reaction　(OER).　As　an　inexpensive　bifunctional　catalyst　with　noble-metal-like　electrocatalytic　properties,　two-dimensional　layered　double　hydroxides　(LDHs)　have　received　considerable　attention.　Here,　a　simple　electrodeposition　method　is　proposed　to　synthesize　a　La-doped　NiFe　LDH　(NiFeLa　LDH)　on　a　nickel　foam.　NiFeLa　LDH　exhibits　excellent　water　splitting　performance　due　to　the　synergistic　effect　of　La　and　laminate　metal,　with　the　best　overpotential　of　399　mV　for　OER　and　223　mV　for　HER　at　a　current　density　of　50　mA　cm(-2),　along　with　excellent　durability　in　alkaline　solution　tests　for　24　h.　The　electrochemical　performance　analysis　and　other　characterization　results　confirm　that　La　doping　can　change　the　electronic　structure　of　LDH　laminates.　According　to　density　functional　theory　calculations,　the　remarkably　enhanced　catalytic　performance　of　NiFeLa　LDH　is　ascribed　to　the　decrease　in　the　activation　energy　of　adsorbed　oxygen　due　to　the　adsorption　of　hydroxide,　making　the　transformation　from　*OH　to　*O　the　rate-determining　step　of　the　OER　process　with　a　four-electron　mechanism.　Additionally,　the　electrolyzer　with　NiFeLa　LDH　as　both　anode　and　cathode　provides　good　stability　as　well　as　a　reduced　cell　voltage　of　1.921　V　to　provide　a　current　density　of　50　mA　cm(-2).　Overall,　this　study　offers　a　simple,　convenient,　rapid,　and　environmentally　friendly　method　for　fabricating　high-performance　water　splitting　catalysts.