Baili Xi 百里奚, also written 伯里 (some authors say, Bai 伯/百 was his family name, Li 里 was his personal, and Xi 奚/傒 or Jingbo 井伯 his courtesy name; it might be that he was identical to a person called Baili Shi 百里視, courtesy name Mengming 孟明 or Mengmeng 孟盟; xi 奚 was actually a designation for slaves), was a high minister of the state of Qin 秦 during the Spring and Autumn period 春秋 (770 - 5th cent. BCE).
His biographies say he grew up under miserable conditions. Later he became a grand minister (dafu 大夫) in the statelet of Yu 虞, but the lord of this polity rarely accepted his memorials. In 655, when Duke Xian of Jin 晉獻公 (r. 676-651) conquered Yu, Baili Xi was captured. He was selected to become a bridal servant (ying 媵) of the future consort of Duke Mu of Qin 秦穆公 (r. 659-621), a princess from Jin, yet because of his humble origin he felt ashame, and fled when on the way to Qin. He was then in Yuan 宛 (modern Nanyang 南陽, Henan) accidently arrested by militia bands of the state of Chu 楚.
When Duke Mu heard about his great abilities, he offered the black skins of five sheep to buy him back, and wanted to appoint him his highest minister. Baili Xi was therefore also called the "Five-Sheep Minister" (wugu dafu 五羖大夫 or wuyang dafu 五羊大夫). Another story says that Baili Xi sold himself and was eventually bought by Gongsun Zhi 公孫枝, who recognized his capabilites and presented him to the duke. Instead of accepting the Duke's offer, Xi recommenced his friend Jian Shu 蹇叔, whom Duke Mu then made senior grand master (shang dafu 上大夫).
The internal disturbances in the state of Jin 晉 were vividly observed by Qin. In 651 Prince Wuyi 夷吾 from Jin found exile to Qin, which allowed his successful return and the accession to the ducal throne (as Duke Hui 晉惠公, r. 651-637). In 648 famine afflicted the state of Jin, and its duke requested support from Qin. Baili Xi permitted the shipment of grain to Jin, and so paved the way of Duke Mu's access to hegemonial overlorship (ba 霸).
As a military commander Baili Xi proved not so successful. In 628 he and Xiqi Shu 西乞術 (Jian Shu's son?) undertook a campaign against the state of Zheng 鄭. The merchant Xian Gao 弦高 tricked Qin, reporting that Zheng was well prepared. The generals thereupon destroyed the statelet of Hua 滑 and returned. On the way they lost the battle with Qin at the foot of Mt. Yao 殽. Baili Xi was captured, but soon returned. A battle against Jin in 625 was lost, but a year later, Qin was victorious.
Baili Xi served for more than ten years as counsellor to the duke of Qin. When he died, everyone in Qin felt sad. A very popular tale says that Baili's wife, Ms Du 杜氏, was searching for him for years and wandered through all regional states until she arrived in Qin, where she served as a laundress in the ducal palace. She finally recognized her husband when he was singing a song.