A method for purifying a modified major mite allergen obtained by the genetic recombination technique and a purified modified major mite allergen obtained by said method for purification are provided. A method for purifying a modified major mite allergen obtained by the genetic recombination technique, which comprises the purification steps: (1) Washing and recovering inclusion bodies containing a modified major mite allergen obtained by the genetic recombination technique with MF membrane; (2) Dissolving said inclusion bodies followed by refolding; (3) Concentrating a solution containing the modified major mite allergen with simultaneous removal of low molecular weight components with ultrafiltration membrane; (4) Recovering the modified major mite allergen in non-adsorbed fractions with an anion exchanger; (5) Recovering the modified major mite allergen in adsorbed fractions with a hydrophobic gel; and (6) Recovering the modified major mite allergen in adsorbed fractions with an anion exchanger, and a modified major mite allergen with high purity obtained by said method for purification.