Objective To address the cumbersome manual pre-column derivatization steps and poor derivative stability encountered in traditional chromatography when determining biogenic amines, so as to improve the efficiency and accuracy of detection.Methods In this study, an amino acid analyzer method is established for the simultaneous determination of eight biogenic amines (i.e., putrescine, histamine, cadaverine, spermidine, octopamine, spermine, tyramine, and phenylethylamine) in aquatic animal products. The aquatic animal product samples are extracted using a sulfosalicylic acid solution, which is followed by high-speed refrigerated centrifugation, elution with potassium salt buffer, separation using a potassium ionic sulfonic acid based strong acid cation exchange chromatographic column, online derivatization with ninhydrin at 130 ℃, and detection at 570 nm.Results The linear ranges for the eight biogenic amines are 1.0~50.0 mg/L with correlation coefficients (R²) greater than 0.994 7. The limits of detection range from 2.5 to 5.0 mg/kg, and the limits of quantification range from 8.3 to 16.7 mg/kg. The spike recovery rates for the three matrices range from 62.2% to 119.2%. The derivatization conditions and equipment stability are satisfactory, with relative standard deviations (RSD) of peak areas ranging from 0.43% to 3.89% and RSD of retention time ranging from 0.050% to 0.334%.Conclusion This developed method exhibits excellent stability, sensitivity, recovery, and accuracy. It is a rapid and simple approach for the detection of the eight biogenic amines in aquatic animal products.