Herein,　a　facile　protocol　of　simple　DNA　adsorption　on　UV-initiated　polymerization　supports　was　proposed　for　effectively　fabricating　aptamer-based　affinity　monolithic　column.　Hydrophilic　cationic　monolith　with　an　excellent　mechanical　stability　was　achieved　within　7　min　and　then　massive　aptamers　were　directly　bound　by　DNA　charge-dependent　adsorption.　Strong　cationic　quaternary　ammonium-based　monomer　was　employed　to　provide　effective　and　stable　positive　charge　surface　for　aptamer　immobilization　in　a　wide　range　of　pH.　An　ultra-high　aptamer　coverage　density　of　6813　pmol/μL　was　achieved　to　gain　a　highly　specific　online　recognition　performance.　Limitations　such　as　low　aptamer　capacity,　tedious　modification　and　time-consuming　reactions　in　the　traditional　biological　or　covalent　modification　strategies　were　avoided.　By　using　ochratoxin　A　(OTA)　as　the　given　analyte,　the　selective　recognition　and　high　recoveries　were　successfully　achieved,　and　little　cross-reactivity　towards　OTB　analogue　was　only　0.5%　even　if　the　content　of　OTB　got　up　to　125　folds　of　OTA.　Applied　to　sample　analysis,　the　satisfactory　discriminations　of　trace　OTA　were　obtained　at　93.9　±　1.9%　–　96.5　±　1.7%n　=　3in　beer,　wheat　and　chicken　liver　samples.　It　might　light　a　cost-effective　access　to　efficiently　preparing　high-performance　affinity　monoliths　towards　the　selective　in-tube　microextraction　of　OTA.　©　2021　Elsevier　B.V.