An　efficient　photoelectrochemical　aptasensor　with　triple　signal　amplification　was　developed　for　sensitive　determination　of　ochratoxin　A　(OTA).　Briefly,　gold　nanoparticles　were　decorated　onto　the　GO-CdS-MoS2　nanocomposites　to　form　GO-CdS-MoS2-AuNPs　nanostructure,　which　was　utilized　as　the　photoelectrochemical　matrix　to　immobilize　the　auxiliary　DNA　(aDNA)　for　the　following　hybridization　with　the　complementary　OTA　aptamer　(OTA　Apt).　Then,　porphyrin　(TMPyP)　molecules　employed　as　an　efficient　photosensitizer　can　be　intercalated　into　double-stranded　DNA　(dsDNA).　Thus,　an　enhanced　initial　PEC　signal　was　acquired.　Upon　introduction　of　OTA,　the　aptamer-OTA　complex　was　formed　and　detached　from　the　electrode,　while　the　TMPyP　molecules　releasing　from　the　platform.　The　photocurrent　signal　was　highly　decreased　ascribed　to　the　target　induced　elimination　of　photosensitizer.　Then,　the　SiO2@helpDNA　(SiO2@hDNA)　can　be　assembled　on　the　electrode　through　the　re-exposed　aDNA.　Notably,　the　steric　hindrance　of　the　SiO2　and　hDNA　may　effectively　depress　the　electron　transfer,　thus　obviously　enlarge　the　decrement　of　the　photocurrent　responses.　Under　optimized　condition,　the　program　shows　satisfied　analytical　performance　for　OTA　with　a　low　detection　limit　of　0.00021　ng　mL−1.　Meanwhile,　it　also　presents　outstanding　reproducibility,　stability　and　specificity.　Importantly,　the　sensing　platform　provides　a　new　ideal　for　detection　of　toxins.　©　2019　Elsevier　B.V.