OBJECTIVE:To develop a method for the determination of paraquat in human plasma,and to provide experimen-tal evidence for the therapy and prognosis of paraquat-poisoned patients. METHODS:The human plasma samples were processed using Waters Oasis solid phase extraction column. HPLC determination was performed on DiamonsilTM C18 chromatographic column with mobile phase consisted of 0.1 mol/L phosphate buffer(containing 80 mmol/L sodium heptanesulfonate,pH adjusted to 3.0 by triethylamine)-acetonitrile (82∶18,V/V) at the flow rate of 0.9 ml/min. The detection wavelength was set at 258 nm. RESULTS:The linear range of paraquat were 20-5 000 ng/ ml;RSDs of inter-day and intra-day both were lower than 9%;average extraction recoveries were 90.72%-96.34%,and average method recoveries were 100.32%-103.10%. CONCLUSIONS:The solid phase ex-traction HPLC can determine the content of paraquat in human plasma rapidly and accurately.