Abstract: A method for the determination of 4-hexylresorcinol in aquatic products was established by high performance liquid chromatography with fluorescence detection.The sample was extracted with acetonitrile and then the solvent extraction was evaporated to dryness.The residue was dissolved with the mobile phase followed by a clean-up step using n-hexane.The diluted solution was determined by HPLC.Chromatographic separation was carried out on a C18 column (250mm×4.6mm, 5μm) with elution of methanol-water solution (75:25, v/v) at a flow rate of 1.0mL/min.The fluorescence detection was performed at an excitation wavelength of 280nm and an emission wavelength of 310nm.4-hexylresorcinol was quantified by the external standard method.The calibration curves showed good linearity in the concentrations range of 0.05 ~ 5.0μg/mL for the standard solutions.The correlation coefficents (R2) was 0.9998.The average recoveries were 90.9% ~ 108.4% at spiked levels of 0.1, 0.2, 1.0 and 5.0 mg/kg.The relative standard deviations (RSD, n=5) were 0.8% ~ 8.1%.The limit of quantification (LOQ) was 0.1mg/kg.