The　high　efficiency　of　the　photoanode　material　is　of　great　significance　for　photoelectrochemical　(PEC)　water　splitting.　Herein,　a　CQDs/Au/TiO2　nanorod　array　composite　photoanode　was　constructed　with　special　attention　to　local　photothermal　effects.　The　intensity　and　characteristics　of　the　local　thermal　effect　generated　by　the　photothermal　conversion　of　plasmonic　Au　nanoparticles　(Au　NPs)　and　carbon　quantum　dots　(CQDs)　are　accurately　represented　by　an　equivalent　simplified　temperature　field　model　constructed　innovatively.　Further　studies　demonstrated　that　the　local　thermal　effect　not　only　stimulates　the　activity　of　the　small　polaron　semiconductor　TiO2,　but　also　accelerates　the　charge　transfer　and　surface　dynamic　reaction　from　the　aspects　of　kinetics　and　thermodynamics.　Simulation　and　experimental　results　also　showed　that　the　surface　plasmon　resonance　(SPR)　effect　of　Au　NPs　and　the　up-conversion　fluorescence　characteristics　of　CQDs　can　cooperate　to　improve　the　carrier　concentration.　Meanwhile,　the　formation　of　a　Schottky　heterojunction　between　Au　and　TiO2,　and　CQDs　as　hole　collectors　synergistically　promoted　the　bulk　charge　separation.　Therefore,　the　CQDs/Au/TiO2　photoanode　achieved　a　remarkable　H-2　evolution　rate　of　641.9　mu　L　h(-1)　cm(-2)　under　AM　1.5　illumination,　five　times　higher　than　that　of　the　pure　TiO2　photoanode.