A　Fe-loaded　Bi2O2S　nanosheet　photoanode　serving　as　photoelectric　biomonitoring　platform　for　the　detection　of　prostate-specific　antigen　(PSA)　using　biologically　inspired　prussian　nanoparticle　(PB)-catalyzed　biocatalytic　precipitation　strategy　was　developed.　Primarily,　the　signal　probe　PB-mAb2　obtained　by　electrostatic　adsorption　was　immobilized　on　a　microplate　in　the　presence　of　target　PSA,　and　4-chloro-1-naphthol　(4-CN)　was　oxidized　to　benzo-4-chloro-hexadienone　(4-CD)　with　the　assistance　of　exogenous　hydrogen　peroxide,　which　was　generated　by　a　large　number　of　hydroxyl　radicals　catalyzed　by　PB.　The　generated　4-CD　showed　strongly　low　conductivity　characteristics　to　burst　the　photocurrent　of　highly　photoactive　Fe-Bi2O2S　photoanode.　The　split　incubation　re-action　could　be　suitable　for　high　volume　and　low-cost　rapid　detection.　A　dynamic　response　range　of　0.1-100　ng　mL-1　with　a　limit　of　detection　of　34.2　pg　mL-1　was　achieved　with　the　sensor　based　on　a　photoelectric　sensing　platform　and　a　biomimetic　catalytic　precipitation　reaction.　Equally　important,　the　sensor　also　showed　good　potential　in　the　detection　of　real　samples　compared　to　commercially　available　ELISA　kits.　In　conclusion,　this　work　provides　a　fresh　scheme　for　the　development　of　sensitive　biosensors　through　a　bio-inspired　catalytic　strategy　of　versatility　and　a　photoanode　coupling　with　high　photoelectric　activity.