Zhang Yu 張禹, courtesy name Ziwen 子文, was a high minister and a Confucian scholar of the late Former Han period 前漢 (206 BCE-8 CE).
He hailed from Henei 河內 (modern Jiyuan 濟源, Henan) and was as disciple of Shi Chou 施讎, an expert in the Confucian Classic Yijing 易經 "Book of Changes". He was also instructed in the Lunyu 論語 "Confucian Analects" by Wang Yang 王陽 and Master Yong 庸生.
During the late years of Emperor Zhao 漢昭帝 (r. 87-74 BCE) he excelled in the local examination and was appointed erudite (boshi 博士) at the National University (taixue 太學). Emperor Yuan 漢元帝 (r. 49-33 BCE) appointed him teacher of the Heir Apparent and Grand master of splendid happiness (guanglu dafu 光祿大夫). Later on he became neishi of the Prince of Dongping 東平.
Under Emperor Cheng 漢成帝 (r. 33-7 BCE), his former pupil, he was given the title of Marquis within the passes (guanneihou 關內侯) and appointed Palace steward (jishizhong 給事中) as director of the Imperial Secretariat (shangshusheng 尚書省). In 25 BCE he succeeded Wang Shang 王商 in the position of Counsellor-in-chief (chengxiang 丞相) and was conferred the title of Marquis of Anchang 安昌侯. Five years later he retired because of illness. He died in 5 BCE.
His posthumous title is Marquis Jie 節侯.
As a Confucian scholar he tried to reconcile the two versions of the Lunyu, that of Qi 齊 and that of Lu 魯, and created the version of Marquis Zhang, Zhang hou Lun 張侯論.