The invention relates to a method for preparing an oxalic acid-induced phenylalanine dipeptide composite material having different charges used for electrochemical chiral recognition. The method comprises the following steps: preparing an oxalic acid-modified electrode, preparing phenylalanine dipeptide solutions having different charges, preparing an oxalic acid-induced phenylalanine dipeptide composite material having different charges modified electrode, and performing identification on a tryptophan enantiomer by an electrochemical method. The method has the beneficial effects that the preparation method of the oxalic acid-induced phenylalanine dipeptide composite material having different charges modified electrode is simple and environmentally friendly; the phenylalanine dipeptide hascertain chiral environment, and the oxalic acid-induced phenylalanine dipeptide composite material having different charges modified electrode has good identification capability on the tryptophan enantiomer.