A pullulan derivative having one or more active sites resulting from introduction of sulfuric acid, phosphoric acid, a sulfonic acid or a carboxylic acid, wherein one hydrogen atom of the group of the formula ##STR1## occurring at said active sites is partly substituted by a group of the general formula ##STR2## wherein L.sup.1 and L.sup.2 each independently is ammine or a unidentate ligand amine or combinedly represent a bidentate ligand amine and Y is an anionic ligand, and/or two hydrogen atoms of the group ##STR3## or of two ##STR4## groups bound to one and the same carbon atom or to two neighboring carbon atoms as occurring at said active sites are, each independently, partly substituted by a group of the general formula ##STR5## wherein L.sup.1 and L.sup.2 are as defined above, and a pharmacologically acceptable salt thereof.The above compound has anticancer activity and is useful as anticancer agents.The present invention is concerned with said compound, a process for producing the same and a pharmaceutical use thereof.