King Zhuang of Chu (Chinese: 楚莊王; pinyin: Chǔ Zhuāng Wáng, died 591 BC) was a monarch of the Zhou Dynasty State of Chu during the Spring and Autumn period of ancient Chinese. His personal name was Xiong Lü, ancestral name Mi (芈), and King Zhuang was his posthumous title. He became one of the Five Hegemons and attempted to wrest control of China from the king of Zhou.
King Zhuang ascended the throne in 613 BC at a time when the Kingdom of Chu was in disarray. For the first three years of his reign, Zhuang wasted time on excessive hunting and lavish partying. Several courtiers were anxious about the king but none dared speak up as he had given orders that anyone who challenged his authority would be killed. When a particularly senior minister challenged him through a riddle, the king responded that he had been waiting for three years for someone from his court to show some nationalistic pride.
The king made Sunshu Ao chancellor and began a series of reforms. Chu's agricultural output improved significantly during his reign, aided by Sunshu Ao's comprehensive dam-works and an enormous planned reservoir created in modern-day northern Anhui province. In 611 BC he annexed the State of Yong (庸国), a move which made Chu much stronger.
After some overwhelming victories at the head of his army, King Zhuang attempted to take the place of King Ding of Zhou. He asked a messenger from Zhou about the weight of the Nine Tripod Cauldrons which Zhou possessed, a euphemism for seeking ultimate power in China at the time but was rebuffed.
In the Battle of Bi, his army defeated the State of Jin, another strong state at that time. Later he achieved hegemony amongst some other states. His progress from lazy regent to a hegemon of his time gave rise to the Chinese Four-character idiom of yī mǐng jīng rén (Chinese: 一嗚驚人; literally: "Amaze [the others] with one cry").