In the history of the ancient Chinese classical documents, the signature did not start from the beginning, but came to appearance through a long development process, gradually evolving from simple to mature. It shall base on the original documents to explore the signature origin, style and characteristics of the classical documents. Until the Sui and Tang Dynasties, the signature method of four books, poems and essays, and other literary forms was basically established, each having individual distinctions. The signature of the four books in the Warring States Period and the Han Dynasty used surname or name and it was originally signed by other people, then later, signed by the author himself. It gradually became common practices in the Wei and Jin Dynasties. In terms of its method, it maintained using the name as signature until the Tang and Five Dynasties, which was simple without official title or other revealing information about the author’s identity. Documents presented to the Emperor were not included.  It was the poetry that had the most complex and diverse signatures, including autograph and surrogate signatures. In the existing stone inscriptions, assigned poems, responsorial poems, offering poems, presentable poems, inscription poems and etc. generally preserved the original features of autographs of the Tang poetry, while poetry manuscripts from Dunhuang mostly had surrogate signatures. In terms of methods, there were name signature, courtesy name signature and official title signature, the last of which also had a difference between the simple and complex versions. Signatures of ode, exposition and argumentation were primarily signed by others in name or official title with a relatively simple version as that of the poetry, because most of the existing Dunhuang manuscripts were private copies. Signatures of monument, inscription, praise, epitaph, brief biographical sketch of a deceased person were similar to those of the imperial edict, imperial mandate, memorial to an emperor, petitions to throne and other official documents, which were most onerous that should list all the official titles one by one. In several signature methods, the most efficient way to identify the author was to sign the official title ″officer so-and-so″ than simply signing one’s name. Compared with the way of listing all the official titles used by monument, inscription, praise and etc. it effectively avoided the cumbersome drawbacks. This way of signature gradually became the general style to sign documents in later generations.  Because of the prosperity of printing in the Song Dynasty, the distinction between the four books and essays and poems was fading away. The literature signature became more and more diverse and complicated. However, basic ways undoubtedly inherited that of the Sui and Tang Dynasties. On the other hand, compared with the printed document, handwriting manuscript had a more complex, casual and diverse signature way with multiple uncertain liquidity characteristics. All in all, the emergence of independent signature of the ancient Chinese classical documents and the style formation of it were closely related to the development of academic and literary forms. Each signature style and its wide application experienced a long historical process. Behind each of them, there was an academic history and cultural history.