Abstract: Using HCl as the medium, the determination of antimony in production water by sequence injection- hydride generation atomic fluorescence spectrometry has been reported. Operating conditions of the instrument were evaluated by orthogonal experiments. Effects of acidity, KBH4 concentration, and thiourea-ascorbic acid content, etc. on measurement results were studied. The effect of coexistent elements was also investigated. Under optimum conditions, the detection limit was 0.011 ng/mL with a linear range of 0～8 ng/mL. The relative standard deviation was 2.78%～6.20%, the recovery rate was 91.0%～99.1%. The method is simple, sensitive and accurate. No significant difference appears between this method and the microwave digestion method.