Zhenjiu jiayi jing 針灸甲乙經 "Numbered book on acupuncture and moxibustion", shortly called Jiayijing 甲乙經 "The A-B classic", is the oldest surviving writing on acupuncture and moxibustion. It is a relatively complete description of these two fields of Chinese medicine. The book was written by the Western Jin period 西晉 (265-316) writer and physician Huangfu Mi 皇甫謐. It was finished around 260 with the original title Huangdi sanbu zhenjiu jiayi jing 黃帝三部針灸甲乙經 "The Yellow Emperor's 黃帝 numbered book on acupuncture and moxibustion in three parts". The received version is 12 juan "scrolls" long and includes 128 chapters. The original book was 4 juan long, each scroll numbered according to the Heavenly stems (jia 甲, yi 乙, bing 丙, ding 丁). The three parts of the book are Suwen 素問 "Simple questions", Zhenjing 針經 "The book of acupuncture" (also known as Lingshu 靈樞 "Pivot of the numinous"), and Mingtang kongxue zhenjiu zhiyao 明堂孔穴針灸治要 "Important treatment methods with needles and moxa for the holes of the Luminous Hall". It includes theoretical chapters as well as concrete methods of treatment, describes the channels of the viscera (zangfu jingluo 臟腑經絡), examination methods (zhenfa 診法), the position of the acupuncture points (shuxue 腧穴), the right application of needles and moxa, pathogeny (bingyin 病因) and pathology (bingli 因病), symptoms of diseases (zhenghou 癥候) and their treatment.
The Jiayijing is a systematic record of all former knowledge on acupuncture and moxibustion and was therefore also the basis for further developments. It includes information provided in the famous medical classic Huangdi neijing 黃帝內經 and is, in some respect, an early commentary to it. It was printed and revised during the Northern Song period 北宋 (960-1126), and the print from 1069 is the base of all later editions, of which more then ten exist. The earliest surviving specimen is a print by Wu Mianxue 吳勉學 in his collection Gujin yitong zhengmai quanshu 古今醫統正脈全書 from the Ming period 明 (1368-1644). The Renmin weisheng press 人民衛生出版社 has published severeal modern editions over the last decades.