A matrix assisted laser desorption ionization-Fourier transform ion cyclotron resonance mass spectrometric(MALDI-FTICR-MS) method was developed for rapid determination of paraquat in whole blood and urine.The sample was extracted by liquid-liquid extraction method,with acetonitrile solution containing 1% formic acid as extraction solvent.Prior to analysis,the extracted solution was mixed with 2,5-dihydroxybenzoic acid.Results showed that there were good linear relationships for paraquat in whole blood and urine samples in the mass concentration range of 10-5 000 μg/L,with correlation coefficients(r) of 0.995 5-0.999 2.The limits of detections(LODs) and limits of quantitations(LOQs) of the method were in the ranges of 0.6-3.0 μg/L and 2.0-10 μg/L,respectively.The average recoveries at spiked levels ranged from 85.2% to 110%,with relative standard deviations(RSDs) of 0.40%-7.3%.The method showed the advantages of low sample and solvent consumption,simple operation,rapid analysis and high sensitivity,and could meet the requirements for rapid detection of clinical poisoning and forensic.