《三元經》是明清時期十分流行的一部道經。本文針對北京中國國家圖書館及北海分館保存的十三種版本，對《三元經》諸本中篇章結構、扉畫造型、文末牌記等內容予以比對和分析，初步研判其成書年代當在明正統十年前後至景泰四年這八年間（至多上溯二三十年）。《三元經》成書後迅速流傳於當時社會的各個階層，並在傳抄過程中經歷了一次文本形式的大轉變：即由先前的「繁本」逐步過渡乃至定格為「淨本」。這次文本的轉型當介於明朝「正德」至「萬曆」年間，至少歷時百年之久。當然，《三元經》「淨本」出現後，無論從其內容抑或文字等方面亦在不斷增衍。研究《三元經》版本之演變，對於理解《道藏》、《續道藏》編纂及明清道經有著積極意義。

San Yuanjing （三元經）was a very popular Daoist Texts during the period of Ming and Qing Dynasties. This dissertation contrasts and analyzes the chapter structures, models of door leaf pictures, written foot cards and etc. of thirteen copies kept by China National Library（中國國家圖書館）and Beihai branch library（北海 分館）and judged tentatively that this book may come into being during the eight years from Ming Dynasty of Zhengtong ten year（正統十年）to Jingtai four year（景 泰四年）, tracing back by twenty or thirty year at the most. As a book, after San Yuanjing （三元經）came into being, it spread at each stratum of society at that time and went through a great transition of text form in the course of documenting, which means the former “Fanben”（繁本）carry out the transition progressively to “Jingben” （淨本）. This text transition lies between the year of ZhengDe（正德）to WanLi （萬曆）in Ming Dynasty and last a century at least. Certainly, after the “Jingben ” （淨本）, San Yuanjing（三元經） also spread out from content to characters. It has positive meaning to understand the Daoist Scriptures（道藏） and to compile the Continuing Daoist Scriptures（續道藏）and Daoist Texts of Ming and Qing Dynasties by researching the edition transition of San Yuanjing （三元經）.