Cao Zhang is a minor character in the 14th-century Chinese classic novel Romance of the Three Kingdoms by the late Luo Guanzhong, and its multiple adaptations. He is Cao Cao's fourth son.
Cao Zhang distinguished himself in his youth in archery and in armed duel. Although Cao Cao criticized his lack of interest in academic studies, Cao Zhang could imagine no other career than a military one. He married a daughter of Sun Ben, a general of Wu warlord Sun Quan, with whom Cao Cao sought understanding before the Battle of Chibi. She gave birth to his sons Cao Kai, Cao Wen and Cao Ti.
When the Wuhuan tribes rose to the northern border of the Wei kingdom, Cao Zhang led an army of infantry and cavalry against them as General of the Determined Cavalry. But because the rebels outnumbered, Cao Zhang retreated into defensive and defended all major passes and routes. Because the rebels stopped coming, they gave up and retreated. Cao Zhang, although wounded, led the persecution. Xianbei tribe leader Kebineng surveyed a 10,000-strong army consisting primarily of riders to follow developments. Seeing Cao Zhang's glorious victory, he submitted to him. Thus, the troubled times on the northern border were over.
Cao Zhang rushed west to join Liu Bei in the Hanzhong campaign. When he reached Chang'an, he realized that the war was already lost. Cao Cao nevertheless promoted him to the general of the elite cavalry and left him in Chang'an to defend it against further attacks by Liu Bei's forces. When Cao Cao returned to Luoyang, Cao Zhang was still on his way, but Cao Cao died of illness. His successor, Cao Pi, sent all his brothers, including Cao Zhang, back to their previous posts, fearing that they would be fighting over his position. He appointed Cao Zhang to King of Rencheng. The following year, Cao Zhang fell ill when he wanted to go to the imperial court in the capital. He died soon after and received posthumously title "Prince Wei".
Cao Zhang's grandson Cao Fang, a son of Cao Kai, was later adopted by Emperor Cao Rui and succeeded him on the throne.
- He became famous for victories against the Wuhuan tribes, but deemed an unworthy heir due to his disinterest in studies. There are several rumors surrounding his death, the most famous tale though, involved him being poisoned by Cao Pi.