Easy-preparation　magnetic　solid-phase　extraction　(MSPE)　adsorbents　with　excellent　extraction　performance　are　very　indispensable　for　MSPE　techniques.　Herein,　a　magnetic　carbon　nanotube　covalent　organic　framework　composite　(MCNTs@TpPa-1)　was　prepared　simply　and　rapidly　through　mechanochemical　synthesis　as　MSPE　adsorbent　for　enriching　microcystins　(MCs).　The　synthesized　MCNTs@TpPa-1　exhibited　well　water　dispersibility,　high　affinity　with　MCs　and　large　surface　area,　resulting　in　outstanding　extraction　performance　for　MCs.　Subsequently,　combined　with　high-performance　liquid　chromatography　with　tandem　mass　spectrometry　(HPLC-MS/MS),　an　efficient,　sensitive　and　convenient　MSPE　method　was　set　up　for　the　determination　of　trace　MCs　from　aqueous　sample,　which　exhibited　acceptable　repeatability　(RSDs　(relative　standard　deviations)　≤　6.8%,　n　=　6),　low　limits　of　detection　(LODs,　0.8–1.5　pg　mL−1),　reliable　linearity　(R　≥　0.9991)　and　broad　range　of　linearity　(2.0–1000　pg　mL−1).　Furthermore,　the　developed　method　was　applied　to　lake　samples　and　trace　MCs　(9.6–24.6　pg　mL−1)　were　found　with　satisfactory　recovery　(85.0–106.0%).　The　results　indicated　powerfully　MCNTs@TpPa-1　was　of　significant　potential　as　an　MSPE　sorbent　for　detection　of　trace　MCs　in　water.　Moreover,　considering　the　complexity　of　traditional　preparation　methods,　novel　prospects　for　preparing　magnetic　covalent　organic　frameworks　(COFs)　with　excellent　extraction　properties　were　opened　up.　©　2021