The invention provides a method for identifying plant varieties. On the basis of electrochemical analysis, a plant leaf tissue extract is immobilized on the surface of an electrode, redox reactions (chemical signals) of an obtained modification electrode in different buffer solutions are converted into electric parameters, whether two samples have identical electrochemical information or not is compared, and thus multiple plants can be classified or identified. The method provided by the invention is simple and feasible, and plants with approximate morphologies or incomplete morphology properties can be rapidly identified.