Abstract: A method of hydride generation atomic absorption spectrometry for the determination of Sb(Ⅲ) and Sb(Ⅴ) was proposed in this paper.Sodium fluoride as masking agent was added both in acidic hydride generation (HG) mode for determining Sb(Ⅲ) and in alkaline HG mode for determining total Sb.Antimony(Ⅴ) was obtained via calculation of difference.The optimum conditions for Sb(Ⅲ) and total Sb determinations and interferences of the coexisting ions were systematically studied.Linearity of the calibration curves was ranged in 0~20 μg·L-1 for acidic HG mode and 0~80 μg·L-1 for alkaline HG mode,respectively,with detection limit of 0.31 μg·L-1 for Sb(Ⅲ) and 0.69 μg·L-1 for Sb(Ⅴ),respectively.The method has been used to determine Sb(Ⅲ) and Sb(Ⅴ) in water and soil samples with satisfactory results and RSD′s less than 5%.