Pd　nanoparticles　supported　on　defective　TiO2　with　oxygen　vacancies　(TiO2-OV)　have　been　prepared　by　an　oxygen　vacancies　mediated　reduction　strategy.　The　resulting　Pd　TiO2-OV　catalyst　with　uniform　Pd　nanoparticles　deposition　demonstrates　a　remarkably　thermocatalytic　activity　toward　rapid,　efficient　reduction　of　nitroaromatics　in　water.　The　reaction　proceeds　efficiently　using　HCOONH4　as　a　hydrogen　source　under　ambient　conditions.　The　controlled　experiments　show　that　the　(CO2-)-C-center　dot　radicals　produced　by　dehydrogenation　of　HCOONH4　are　the　main　active　species　for　the　selective　nitro　reduction.　Moreover,　defective　TiO2　nanostructures　deposited　with　Pd　nanoparticles,　featuring　excellent　visible-light　absorption　via　the　creation　of　oxygen　vacancies,　can　take　advantage　of　the　solar　and　thermal　energy　to　drive　catalytic　reduction　reactions　more　efficiently　at　room　temperature.　During　this　process,　the　oxygen　vacancies　and　Pd　nanoparticles　play　synergetic　roles　in　the　photoreduction　of　nitro　compounds.　Our　work　would　be　beneficial　for　implementation　of　a　novel　defect-mediated　catalytic　system　in　which　solar　light　energy　can　be　coupled　with　thermal　energy　to　drive　an　energy　efficient　catalytic　process.