The present invention provides a pharmaceutical composition for respiratory administration comprising a polysaccharide derivative having a group derived from a polysaccharide and a group derived from a physiologically active substance that is covalently bonded to the group derived from the polysaccharide.本発明は、多糖に由来する基と、多糖に由来する基に共有結合する生理活性物質に由来する基とを有する多糖誘導体を含む呼吸器投与用の医薬組成物を提供する。