An object of the present invention is to provide a water-solubilizing preparation that is obtained by convenient steps without use of a special apparatus such as a high-pressure homogenizer, does not impair the original properties of a water-based material even after being added to the material, has high dispersibility and transparency and excellent heat resistance and acid resistance, and can maintain stability. The water-solubilizing preparation of the present invention is a biologically active substance-containing water-solubilizing preparation comprising 1 to 50% by weight of an oily ingredient (A) containing a biologically active substance and oil, 10 to 98% by weight of a polyglycerin fatty acid ester (B) having an HLB value of 12.5 or larger, and 1 to 40% by weight of a surfactant (C) having an HLB value of 7 to 11.8.
