A method for separating and recovering trivalent and tetravalent actinoids in a simple and less costly manner without using an organophosphorus compound is provided. This method selectively separates and recovers the tetravalent actinoid plutonium Pu (IV) and the trivalent actinoids americium Am (III) and curium Cm (III) from trivalent lanthanoids Ln (III), etc. with the use of an extractant having a functional group with neutral multidentate ligand activity which is a hybrid donor type organic compound having both of donor atoms, i.e., an oxygen atom and a nitrogen atom.