A new microemulsion high performance liquid chromatography for the determination of phenols in water has been developed.Separations were performed on a C18 column with microemulsion as mobile phase, column temperature at 35 ℃, flow rate of 1.4 mL/min and measured at wave length of 275 nm.The mobile phase was prepared by dissolving 1.0 g sodium dodecylsulphate (SDS) and 5.5mL methanol in 94.0 mL aqueous HAc-NH4Ac with pH 4.0.The results show that the linear ranges for the determination of hydroquinone, resorcinol, phenol, p-cresol, parachlorophenol were 0.1~10 μg/L, 0.25~16 μg/L, 0.25~12 μg/L, 0.25~30 μg/L, 1.0~30 μg/L.The detection limits (μg/L) were: 0.01 μg/L for hydroquinone, 0.02 μg/L for resorcinol, 0.04 μg/L for phenol, 0.03 μg/L for p-cresol, 0.05μg/L for parachlorophenol.The relative standard deviations of five phenols are less than 5% and of good precision.The method was applied for determination of hydroquinone, resorcinol, phenol, p-cresol, parachlorophenol in the river water.The recovery for each phenol were covered in the range of 93.5~104.7%.