To understand the metabolic elimination pattern of enrofloxacin in Russian sturgeon, with oral administration of 20 mg/kg b.w for 5 consecutive days, the trend of enrofloxacin content in various tissues of Russian sturgeon was determined by high performance liquid chromatography tandem mass spectrometry, and the data were processed by 3p97 pharmacokinetic software. The result showed that with oral administration of 20 mg/kg b.w for 5 consecutive days at 22.5℃ average water temperature, the time to peak of enrofloxacin in the blood, liver and muscle was 4h, 2h and 8h, respectively; the half-lives of the absorption were 2.052 1 h, 1.112 8 h and 1.892 0 h, respectively; and the half-lives of elimination were 53.265 4 h, 203.517 4 h and 49.517 4 h, respectively;the total area under the time curve were 2 025.145,13 529.004和2 328.889 μg/(mL·h), repectively. The recommended withdrawal period for enrofloxacin in Russian sturgeon should be at least 945 days based on the evluation of muscle and fish skin. [Chinese Fishery Quality and Standards, 2023, 13(1): 10-18]