A　novel　aptamer-based　polyhedral　oligomeric　silsesquioxane　(POSS)-containing　hybrid　affinity　monolith　has　been　prepared　with　a　facile　“one-pot”　process　simultaneously　via　“free　radical　polymerization”　and　“thiol-ene”　click　reaction,　and　used　for　on-line　selective　extraction　and　practical　analysis　to　trace　ochratoxin　A　(OTA).　By　using　the　ternary　porogenic　mixture　composed　of　water/DMF/PEG,　a　homogeneous　polymerization　mixture　with　POSS　chemicals,　acrylate-based　monomers　and　aptamer　aqueous　solution　was　obtained,　and　the　copolymerization　of　POSS　chemicals,　polymer　monomers　and　aptamer　aqueous　solution　was　systematically　studied.　Characterizations　such　as　the　morphology,　FT-IR　and　fluorescence　spectra,　mechanical　stability,　dynamic　binding　capacity,　cross-reactivity　and　selectivity　of　the　resultant　affinity　monolith　were　also　evaluated.　Attributed　to　the　porous　monolithic　structure　and　aptamer-based　affinity　interaction,　acceptable　selective　recognition　and　recovery　yields　towards　trace　OTA　were　obtained.　With　a　5-fold　volume　enrichment,　the　limit　of　detection　(LOD)　and　limit　of　quantitation　(LOQ)　of　OTA　in　fortified　beer　samples　were　gained　at　0.025　ng/mL　(S/N　=　3)　and　0.045　ng/mL　(S/N　=　10),　respectively.　It　could　be　competent　for　the　sensitive　measure　of　actual　OTA　residues　in　real　beer　samples.　In　comparison　with　the　previously　reported　strategies　containing　common　“sol-gel”　chemistry,　the　proposed　protocol　to　fabricating　aptamer-modified　POSS-containing　hybrid　affinity　monolith　showed　a　simpler　preparation　with　acceptable　selectivity　and　higher　recovery　to　trace　OTA.　©　2018　Elsevier　B.V.