A method for the determination of species (arsenite (As(III)), arsenate(As(V)), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)) in solution samples of gold mine tailings has been applied. The analytical method used was ion chromatography coupled on-line to atomic fluorescence spectroscopy through hydride generation with the mobile phase (NH4)2 HPO4 (pH 6. 0). The recovery with the standard solution of arsenic added into the water samples was very good (recovery 95%-109%). The arsenic species were separated completely; arsenic speciation was stable and the detection limits were very low: 1.0 microg x L(-1) As(III) and 2.3 microg x I(-1) for As(V). The method is fit for the determination of arsenic species in the solution of gold mine, gold mine tailings and the polluted water around the gold mine.