A method and device for banknote identification based on thickness signal identification, allowing for simple and highly efficient identification and separation of abnormal banknotes by means of combining two thickness identification methods, namely an upward-facing area identification method and a downward-facing area identification method, for banknote identification. The recognition method comprises: collecting a thickness signal of a banknote; preprocessing the thickness signal; utilizing an upward-facing area identification method to identify the thickness signal, thus acquiring an upward-facing processing identification result; utilizing a downward-facing area identification method to identify the thickness signal, thus acquiring a downward-facing processing identification result; merging the upward-facing identification processing result and the downward-facing processing identification result on the basis of a predetermined rule, acquiring a merged result; and, identifying the merged result, thus acquiring an identification result.