「天祿琳琅」是清代乾隆時期宮廷善本藏書之所，而乾隆皇帝命令于敏中等人編撰《天祿琳琅書目》，用以記錄該地藏書之盛。于敏中等人整理「天祿琳琅」藏書之時，需先考出古籍版本的時代，而其應用之法極多，實有值得探討之處，惜歷來學者未能針對此一課題，進行深入的研究工作。本文嘗試整理于敏中等人鑒定版本的方法，並且評議其得失，期使讀者瞭解于氏諸人的學術表現，也能明白《天祿琳琅書目》的學術價值，更能深入認識乾隆時期版本學的發展，已能具有良好的基礎。

Tianlu Linlang refers to a place where books of official edition were collected in the reign of Emperor Qianlong of Qing dynasty. In order to highlight the abundant books in this place, Emperor Qianlong ordered Yu Min-Zhong et al. to compile Bibliography of Tianlu Linlang. When Yu et al. was sorting out books in Tianlu Linlang, it was necessary for them to identify the year of ancient editions. When referring to methods they applied for classification, they are worth to be explored and learned by us. It is a pity that no profound exploration has been performed by previous scholars on this subject. This thesis attempts to list and evaluate the edition identification methods of Yu Min-Zhong et al. In such case, not only can readers understand academic performance of Yu et al., but realize academic value of Bibliography of Tianlu Linlang. Then, we can grasp that the study of edition under Emperor Qianlong of Qing dynasty has prepared the stable ground for future development.