Cao Fang (232-274), also known as Lanqing, was the third emperor of Cao Wei during the Three Kingdoms period. He reigned from 239 to 254 AD and was the adopted son of Wei Ming Emperor Cao Rui. According to the records of "Wei's Spring and Autumn Annals", Cao Fang may be the son of Cao Kai, the king of Rencheng, the grandson of Cao Zhang and the great-grandson of Cao Cao. Cao Fang was named King of Qi in 235. Cao Rui died of illness in 239 and succeeded him as emperor. In 254, Sima Shi deposed Cao Fang as King of Qi and made Cao Mao, the Duke of Gaogui Township, emperor. After Sima Yan proclaimed himself emperor on behalf of Wei, he changed the title of Cao Fang to Shaoling County Duke. In 274, Cao Fang died of illness, and his posthumous title was Duke Li. In 235, Cao Fang was established as King of Qi.

In the first month of 239, Emperor Wei Ming Cao Rui became seriously ill, so he made Cao Fang the crown prince. On the same day, Cao Rui died of illness, so Cao Fang succeeded to the throne at the age of eight. General Cao Shuang and Taiwei Sima Yi assisted in the government. In August of the same year, Cao Fang began to visit the government in person and listen to ministers' reports. In 244, Cao Fang issued an imperial edict to attack Shu on Cao Shuang's suggestion, but failed. In 247, Cao Shuang put Empress Dowager Guo under house arrest in Yong'an Palace, and since then she has monopolized power. Empress Dowager Guo and Cao Fang parted in tears. There was an earthquake that year. In 249, Cao Fang left Luoyang to pay homage to Gaopingling, the tomb of Emperor Wei Ming, and Cao Shuang and his brothers followed. Sima Yi took the opportunity to report to the Empress Dowager Yongning, requesting that Cao Shuang and his brother be deposed, and lead troops to garrison Simamen and control the capital. Cao Shuang finally gave in and asked to be removed from his post. He was soon convicted by Sima Yi and the three tribes were wiped out. From then on, the military and political power of Cao Wei fell into the hands of Sima Yi. In 251, Wang Ling tried to establish Cao Biao, the king of Chu, but was attacked by Sima Yi and Cao Biao was sentenced to death. In the same year, Sima Yi died of illness. In 252, Sima Shi was appointed as the general, and the Sima family continued to control the affairs of the Wei state. In February 254, Zhongshu ordered Li Feng, Empress Zhang's father Zhang Ji and others to plot to abolish Sima Division and make Xia Houxuan the general. When the incident was revealed, many people were implicated and killed, and Empress Zhang was deposed. In the autumn of the same year, Sima Zhao was ordered to attack Jiang Wei and arrived at the capital. Cao Fang was optimistically observing the troops. Xu Yun planned with his cronies to kill Sima Zhao when he was resigning, and led this army to attack Sima Zhao. The edict had been written, but Cao Fang did not implement it out of fear. In September, Master Sima reported to the Queen Mother that she deposed Emperor Cao Fang and made Cao Mao, the Duke of Gaogui Township, the emperor. Cao Fang moved out of Luoyang and built the Qi Palace in Zhongmen, Hanoi County. All the etiquette systems were like those of feudal kings. In 266, the Western Jin Dynasty replaced the Wei Dynasty, and the title of King Cao Fang of Qi was changed to Shaoling County Duke. In 274, Cao Fang died.