PROBLEM TO BE SOLVED: To provide a drug delivery technique capable of efficiently delivering a drug to a tumor tissue without lowering the pharmacological activity of the drug. The drug delivery carrier comprises a biocompatible polymer in which the diol structure of the drug having the diol structure represented by formula (1) and the group capable of forming an acetal bond represented by formula (2) are bound. .. [M and n are independently 0 or 1； * is a bond] [m and n are independently 0 or 1； * is a bond] [Selection diagram] None【課題】薬物の薬理活性を低下させることなく、効率よく腫瘍組織に薬物を送達することができる薬物送達技術の提供。【解決手段】式（１）で表わされるジオール構造を有する薬物の前記ジオール構造と式（２）で表わされるアセタール結合を形成し得る基が結合した、生体適合性ポリマーからなる、薬物送達用担体。［ｍ及びｎは夫々独立に０又は１；＊は結合手］［ｍ及びｎは夫々独立に０又は１；＊は結合手］【選択図】なし
