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A method for solvent extraction of phosphoric acid comprises counter-currently contacting an impure phosphoric acid solution containing at least 45 wt. % of P2O5 with a partially water-miscible solvent in the presence of sulfuric acid, and which is characterized in that (a) as said solvent, a solvent in which from 3 to 10 wt. % of water is soluble, is used, and (b) sulfuric acid is added to a place where the H3PO4 concentration in the aqueous phase is at most 3 mol./l so as to bring the relation between the free sulfuric acid concentration (Y (mol/l)) and the H3PO4 concentration (X (mol/l)) in the aqueous phase of the same place to satisfy the formula 5.0-0.83X>/=Y>/=2.5-0.83X within the range of the H3PO4 concentration in the aqueous phase being from 0.5 to 3 mol/l.