Abstract:A high performance liquid chromatography method for the determination of difenoconazole·flusilazole 40% micro-emulsion was established. The separation and determination of difenoconazole·flusilazole in the samples were conducted by C 18 column with the mixture of methanol and water as mobilephase (85∶ 15,by vol) at the flow rate of 1 mL/min at 220 nm by DAD detector. The results showedthat the retention time of difenoconazole and flusilazole are 6. 320 and 4. 700 min. At the injection con-centration from 10 ~100 mg/L,the linear correlation coefficients for difenoconazole and flusilazole were0. 999 8 and 0. 999 9,the standard deviations were 0. 027 0 and 0. 023 9,the variation coefficients were0. 077 0% and 0. 479 0%,and the average recoveries were 99. 70% and 99. 11%,respectively. In thismethod,difenoconazole·flusilazole with good separation effect,was suitable for quantitative analysis ofactive ingredients in preparation.