A microparticle, comprising an agglomerate of a hydrophilic active substance containing particle, which particle comprises an amphiphilic polymer composed of a hydrophobic segment of poly (hydroxy acid) and a hydrophilic segment of polysaccharides or polyethylene glycol, and a hydrophilic active substance, is characterized by an efficient inclusion of the hydrophilic active substance, and a release of the hydrophilic active substance at an appropriate speed in the human body, and is hence very useful as a DDS pharmaceutical preparation.
