| Zhouyu 州籲 | |
| Succession: | Ruler of Wey |
| Reign: | 719 BC |
| Predecessor: | Duke Huan of Wey |
| Successor: | Duke Xuan of Wey |
| Birth Name: | Zhouyu |
| Death Date: | 719 BC |
| Death Place: | Pu (濮), Wey (now Puyang) |
| Father: | Duke Zhuang I of Wey |
Zhouyu (died 719 BC) was a son of Duke Zhuang of Wey who was briefly the Duke of Wey in 719 BC by murdering Duke Huan of Wey, his elder brother. Less a year into his reign, he was arrested in Chen (state) at the behest of Wey Minister and killed. He was not given a posthumous name due to his being characterized as an usurper and due to his short reign.
Prince Zhouyu was born to Duke Zhuang of Wey and one of his favorite concubines. His father doted on him and allowed him to pursue his military interest unrestrained, though, Duke Zhuang's principal wife, detested him.
When Duke Zhuang was still undecided on which one of his sons to succeed him,, a Wey minister, remonstrated him to either settle on Zhouyu as the heir if he intended on doing so or stop him from further military pursuits, as he could pose a threat to the heir later on. Duke Zhuang did not heed this advice. Eventually, in 735 BC, Prince Wan, Zhouyu's elder brother, succeeded Duke Zhuang. He would become known as Duke Huan of Wey.
, Shi Que's son, associated himself with Prince Zhouyu despite his father's ban. Upon the accession of Duke Huan, Shi Que retired, ostensibly due to age.
In 733 BC, Duke Huan dismissed Zhouyu of all his posts on account of his arrogance, and Zhouyu fled Wey. In exile, he attempted to befriend Gongshu Duan, younger brother of Duke Zhuang of Zheng, after his failed rebellion against him and exile in 722 BC.
In 719 BC, Zhouyu, after gathering fellow Wey exiles, killed Duke Huan and made himself the new duke.
To consolidate his power, Zhouyu tried to make use of prior animosity between Wey and Zheng as well as the support of other states. He persuaded Duke Shang of Song, who had recently acceded to the Song throne, to attack Zheng together with Chen and Cai, his rival Prince Ping of Song having recently fled to Zheng. Further, Zhouyu secured the casus belli of helping Gongshu Duan to take the Zheng throne. However, Zhouyu's attack on Zheng was unsuccessful: the allied force besieged the eastern gate of Xinzheng, Zheng's capital, in summer 719 BC for five days and then retreated. Another attack on Zheng in the autumn of the same year, this time joined by troops from Lu, accomplished no major victory either.
Zhouyu remained unpopular in Wey. Duke Yin of Lu once asked, one of his officials, about whether or not Zhouyu could succeed. Zhong Zhong replied that Zhouyu, depending on cruelty and weaponry to secure his rule rather than virtue, would eventually fail.
Shi Hou, now an official serving Zhouyu, asked his father Shi Que about how to stabilize Zhouyu's rule. Shi Que advised him that a visit to the King of Zhou could do so. When questioned further about how to gain the king's audience, Shi Que suggested visiting Duke Huan of Chen, who was favored by King Huan of Zhou, to ask for an audience through him. Shi Hou agreed with this suggestion: he and Zhouyu went to Chen.
Meanwhile, Shi Que sent someone to declare to Chen that it was Zhouyu and Shi Hou who murdered Duke Huan and to ask Chen to arrest them, which Chen did. Shi Que sent, a retainer of the Shi clan, to Chen in order to execute Shi Hou, while Zhouyu was executed after being returned to Wey. The Chinese chengyu 大义灭亲 ("Killing one's relatives for the sake of justice"), attested in Zuo Zhuan, came from this episode of Shi Que killing his own son for the sake of righteousness.
Later, Wey officials went to Xing (state) to welcome Prince Jin, who was sent to Xing as a political hostage, back to Wey. Prince Jin would become known as Duke Xuan of Wey.