Han Cheng (died 206 BC), also known as Han Wang Cheng in some Chinese historical texts, was a ruler of the Kingdom of Hán (韓國) of the Eighteen Kingdoms during the Chu–Han Contention, an interregnum between the Qin Dynasty and the Han Dynasty.
Han Cheng was a descendant of the royal family of Hán of the Seven Warring States. He lived as a commoner under the Qin Dynasty after his native state was conquered by Qin in 230 BC.
In 209 BC, when uprisings occurred throughout China to overthrow the Qin Dynasty, Han Cheng went to join Xiang Liang's rebel force in the hope of reviving his native state. Along the way, he met Zhang Liang, a descendant of a bureaucrat family from his state. Zhang Liang succeeded in persuading Xiang Liang to restore the Hán kingdom and Han Cheng was appointed as its ruler, with Zhang serving as his chancellor. Xiang Liang also provided some troops to Han Cheng and allowed him to attack the Qin garrisons based at Yingchuan (穎川; in present-day Henan).
After the fall of the Qin Dynasty in 206 BC, Xiang Yu divided the former Qin Empire into the Eighteen Kingdoms. Han Cheng was appointed as "King of Hán" (韓王). Months later, Xiang Yu had Han Cheng killed and replaced with Zheng Chang. By the way, Xiang Liang recommended King Xin of Han as a new King of Han to Emperor Gaozu of Han.