A method using high performance liquid chromatography (HPLC) for thedetermination of butocarboxim in agricultural products was developed. Butocarboximwas extracted from samples with acetone and the extract solution was concentrated.The residue was dissolved in sodium chloride solution and partitioned with n-hexane.The aqueous phase was collected followed by extracted with dichloromethane, whichwas then evaporated to a volume of 2 mL prior to passing through an aminopropylcartridge for sample clean-up. Determination of butocarboxim residue in crops wascarried out by HPLC equipped with a post-column derivatization system and afluorescence detector. HPLC separation was performed on a Lichrospher 60 RP-Select B column eluted with a mobile phase of acetonitrile-water (25:75, v/v).Butocarboxim was hydrolyzed at 90℃ under alkaline conditions and subsequentlyreacted with o-phthaldia ldehyde (OPA) / 2-mercaptoethanol reagent via a post-column reactor to generate a fluorophore, which was then detected with afluorescence detector at Ex 340 nm and Em 455 nm. Average recoveries fromradishes and bamboo sprouts, which were spiked with 0.1~0.3 and 0.2 ppmbutocarboxim, respectively, were in the range of 81.9~82.6%. The detection limit was0.05 ppm. No butocarboxim residue was detected in 10 commercial productsincluding radishes, carrots, and bamboo sprouts.