Abstract: The total residue amount of prochloraz and its metabolites in loofah was determined by gas chromatography （ECD）.The prochloraz and its metabolites in the loofah were extracted with acetone,and the prochloraz and its metabolites were all conversed to 2,4,6-trichlorophenol by pyridine hydrochloride at 210 ℃ to 240 ℃. After liquid distribution purification,content of 2,4,6-trichlorophenol was determined by gas chromatography （ECD）,and then converted to the residue amount of prochloraz. The average recovery of prochloraz in loofah was 73% to 78%,and the relative standard deviation （RSD） was 4% to 6%.The lowest detection concentration of prochloraz in loofah was 0.02 mg/kg. Residue dynamics study showed that the digestion rate of prochloraz in loofah was fast, and after 3 days, the residue amount of prochloraz was not detected.

Key words: gas chromatography（ECD）, prochloraz, loofah, digestion dynamics