Abstract: A method for quantitative analysis of fungicide SYP-Z048 5-(4-chlorophenyl)-2,3-dimethyl-3-(pyridine-3-yl)-oxazoline was developed by a reversed-phase highperformance liquidchromatograph.The chromatogram of SYP-Z048 showed two absorbance peak by a C18ODS column,which belonged to Z and E,respectively.The mobile phase consisted of methanol and water(V/V=75∶25) and the flow rate was 1 mL/min.The wavelength of detector was 220 nm.When concentration of standard solvent ranged from 400～700 μg/mL,there was good linear relationship between concentration of standard solvent and area of absorbed peak.The regression equation was(Y = 4.846 7XX+ 232.85),and the correlation coefficient of the standard curve was(0.999 2).The repeatability SR of technical SYP-Z048 and its formulation were(0.004 0),(0.004 7), respectively. The method was proved to be accurate and precise to successfully measure the SYP-Z048.