In this paper a spectrophotometric method for the Mn(II) determination is proposed. This method is based on the extraction in toluenic Adogen 464 solution of the complex origined between Mn(II) and isophtaldihydroxamic acid. The method permits determination of 50-100 γ of Mn (II). The error and the molar absorptivity are values of 2.0% and 8.500 1. mol.−1.cm−1respectively. The interference levels caused by foreign ions are established. Also the standard line by extraction with ethylacetate Adogen 464 solution was studied.