Wu Guotai, the character in Romance of the Three Kingdoms, can't be found in the official history. In the novel, Wu Guotai is described as Sun Jian's second wife, the sister of Sun Jian's wife Wu Lie (Mrs. Wu in the novel) and the mother of Sun Lang and Sun Ren (Sun Shangxiang).

In Romance of the Three Kingdoms, after the death of Mrs. Wu Taifu, Sun Quan obeyed her mother's orders and adopted Wu Guotai as her biological mother. After Battle of Red Cliffs, Zhou Yu set a honey trap, lured Liu Bei to Wu Dong with Sun Shangxiang as bait, and took the opportunity to imprison Liu Bei in exchange for Jingzhou. After Liu Bei arrived in Wudong, the story of marrying Sun Shangxiang spread all over the city with Zhuge Liang's clever plan. Wu Guotai was furious when he learned that, so he went to talk to Sun Quan. Later, Liu Bei was recognized when he was dating in Kanluoji, which eventually led to the marriage of Sun Liu. After that, Liu Bei and Sun Shangxiang fled back to Jingzhou. When Sun Quan was ready to attack Jingzhou according to Zhang's plan, he intervened to stop him and severely reprimanded Zhang for hurting his daughter's life. Sun Quan had no choice but to send Zhou Shan to Jingzhou, pretending to be seriously ill, and induced Liu Bei's son to return to Wu, in an attempt to coerce Liu Bei to return to Jingzhou, but he was stopped by Zhao Yun and Zhang Fei on the way, and Zhou Shan was killed by Zhang Fei. Sun Quan's plan failed.