Wu Xu 伍胥, as he is also called, was a son of the noble Wu She 伍奢 from the state of Chu 楚. When his father was executed for an alleged crime Wu Zixu fled and visited the states of Song 宋, Zheng 鄭 and Jin 晉 to seek for refuge.
Finally he came to Wu where he became aquainted with prince Guang 公子光 to whom he suggested usurping the throne. Guang killed King Liao 僚 (r. 526-514) and mounted the throne as King Helü 闔閭 (r. 514-496). Wu Zixu became Helü's advisor.
He first took revenge for the unjust death of his father, had conquered Chu in 506, had dug out the tomb of King Ping 楚平王 (r. 528-516) and had flogged the royal corpse. For his military success he was rewarded with the territory of Shen 申. He is therefore also called Shen Xu 申胥.
With the accession of King Fucha 夫差 (r. 495-473), Wu Zixu continued with expansive politics and was able to force King Goujian 句踐 (r. 495- 465) of Yue into submission. Aware of the the limits of the power of the state of Wu, Wu Zixu tried to stop king Fucha from further expansive adventures. The king's armies defeated the state of Qi 齊 to the north, and instead of annihilating Yue first, as Wu Zixu suggested, the king pushed on with the ambition to take over the hegemonship.
At the court, Wu Zixu fell into disgrace and became victim of Bo Pi's 伯嚭 slanders. The king presented Wu Zixu with a sword to kill himself.