Wang Gui (571–639), courtesy name Shujie, posthumously known as Duke Yi of Yongning, was a Chinese official who served as a chancellor during the reign of Emperor Taizong (Li Shimin) in the Tang dynasty.
Wang Gui, having lost his father early in his life, was said to be elegant in his behavior, having few desires and comfortable in his poverty, and not making friends easily with just anyone.
Near the end of the reign of Emperor Wen of Sui, Wang Gui served as a low-level imperial official in charge of ceremonies.
Based on the laws of the time, Wang Gui was to be executed as well, but he fled into the Qinling Mountains and remained in hiding there for more than a decade.
In 618, after news arrived at Chang'an that Emperor Yang had been killed in a coup at Jiangdu (江都, in modern Yangzhou, Jiangsu) led by the general Yuwen Huaji, Li Yuan had Yang You yield the throne to him, establishing the Tang dynasty as its Emperor Gaozu.
Wang and Wei Zheng, another advisor to Li Jiancheng, suggested that he should also try to establish some military achievement of his own and also recruit capable people to serve on staff during the campaign.
Li Jiancheng agreed, and volunteered to attack one of the remaining threats against Tang rule, Liu Heita the Prince of Handong.
He treated Wang with kindness, creating him the Baron of Yongning and made him the deputy head of the examination bureau of government (門下省, Menxia Sheng) as well as an advisor for his son and crown prince Li Chengqian.
Later that year, the head of the examination bureau, Gao Shilian, was demoted after he withheld a petition from Wang, and in 628, Emperor Taizong made Wang the acting head of the examination bureau instead—a post considered as one for a chancellor.
Wang instead responded, "Does Your Imperial Majesty believe that the Prince of Lujiang was correct in seizing this woman?"
Wang and Wen Yanbo spoke against the rebuke, stating that it was not appropriate for Emperor Taizong to have had an important official become a music teacher for ladies in waiting in the first place.
Emperor Taizong was surprised, but the next day indicated to the high-level officials that he was rash and improper in rebuking Wang and Wen.
Wang further advocated ruling the state by Confucian principles, a position that Emperor Taizong agreed with.
In 633, Wang was accused of leaking state secrets, and he was demoted to the post of prefect of Tong Prefecture (同州, roughly modern Weinan, Shaanxi).
In 637, he finished compiling a work on proper ceremonies, and for this contribution Emperor Taizong awarded him with silk and created one of his sons a baron.
That year, he was also made the teacher of Emperor Taizong's favorite son Li Tai the Prince of Wei.