A rapid and sensitive determination of antimony(III) and antimony(V) has been carried out by non-dispersive atomic fluorescence spectrometry using a sodium borohydride reduction. The total antimony amount is determined by pre-reduction of antimony (V) to antimony(III) with potassium iodide, followed by stibine evolution. The stibine evolution from antimony(V) is inhibited by the addition of hydrofluoric acid solution and the selective determination of antimony(III) is made. The antimony(V) amount is determined by calculating the difference between the two values.