The utility model discloses a book separating device which comprises a delivering outer shell (5), a guide block (6) and a transmission mechanism provided with a plectrum (1). A face of the delivery outer shell (5) is a vertical face, wherein the face of the delivery outer shell (5) is next to vertically conveyed books. The transmission mechanism provided with the plectrum (1) is fixed on the delivery outer shell (5), and is matched with the delivery outer shell (5) to lift the books conveyed vertically to the upper surface of the delivery outer shell (5). The guide block (6) is positioned on the upper portion of the upper edge of a vertical face of the delivery outer shell (5), and is fixed on a main device. An acute angle is formed between the guide block (6) and the transmission direction, and the guide block (6) is used for horizontally placing books which are in a vertical state on the upper surface of the delivery outer shell (5). According to the book separating device, usage efficiency of the device can be increased, labor intensity of workers is reduced, and production efficiency is improved. The book separating device is suitable for separating of different books.