The purpose of this research is to estimate the possibility of As (III) extraction by the water - antipyrine - sulfosalicylic acid bottom system from chloride solutions. This study shows the efficiency of As (III) extraction by means of the water – antipyrine – sulfosalicylic acid bottom system. The recovery (89 ± 3) % and distribution coefficient (25 ± 6) of arsenic are determined on model systems using concentrating by in situ method «added- analyzed».