Extraction of trace level persistent organic pollutants is an important issue in water samples. So in this work, p(HEMAPA) monolithic columns were developed as a novel kind of solid-phase extraction adsorbents, as well as p(HEMAPA) solid-phase extraction (SPE) adsorbent was coupled with high-performance liquid chromatography (HPLC) (p(HEMAPA-HPLC) for the determination of benzo[a]pyrene (BaP) on-line mode. After p(HEMAPA-HPLC) para- meters including the injection volume, flow rate, and the sample volume had been optimized in detail, BaP separation procedures on the p(HEMAPA-HPLC) containing mobile phase, different amounts of BaP, and reusability were perfor- med. Advantages of this procedure are low quantitation limits (0.05–1.0 ng/mL), short extraction time, low consump- tion of organic solvents, and ease of automation and operation of the whole analysis. The experimental results indi- cated that p(HEMAPA-HPLC) allowed for one-step BaPs extraction, clean-up and analytical determination under the optimal conditions. The reusability of BaPs from water samples was 99.7% with a negligible capacity decrease after ten adsorption–desorption cycles. The method detection limit (MDL), relative standard deviation (RSD) and recovery were obtained as 0.007 ng/mL, 0.26%, and 97.0%, respectively. It was concluded that p(HEMAPA) monolithic column coupled with HPLC was an excellent alternative for the routine analysis of BaPs at trace level.