The work investigates boric acid and sodium tetraborate distribution oin systems based on technical oxyethylated surfactants (oxyphos B, synthamide-5, synthanols DS-10 and ALM-10) and magnesium salt (chloride, nitrate or sulfate). In example magnesium chloride – oxyphos B – water system dependence of boric acid and magnesium chloride recovery ratesof macro components contents in the system are shown. The influence of boric acid or sodium tetraborate initial concentration and presence of strong acids to boronextraction demonstrated. It was found that boric acid and magnesium chlorideseparation in magnesium chloride – oxyphos B – water system is impossible. Based on analysis of data obtained, it was found that extraction of boric acid increases with increase in extract volume and water concentration in extract.