Deng Ai lost his father in his early years and his family was poor, but he lived in Henan Province for a long time. Deng Ai had been stuttering since childhood and lived in Runan, he moved to Yingchuan with his mother. Deng Ai had a progressive education since he was a child, which had the greatest impact on his own life. Deng Ai first served Cao Cao as a younger official, he helps Cao Cao to attacked Liu Bei and Sun Quan in Chibi. During the Battle of Tianshui, Deng Ai and Guo Huai commanded to save Sima Zhao from conflict of the Shu. At this sense, Jiang Wei, a strategic warrior who only to against Zhao Yun first when he fought with them, Zhuge Liang eventually subdued Jiang Wei.
Jiang Wei decided to joins Shu after being surrendered, Deng Ai agreed with his decision to joined forces with Sima Shi and Sima Zhao to fight against Shu troops, Zhuge Liang died of illness after the battle of Wuzhang Plains. When he sent as a messenger to the capital, Luoyang, where he happened to meet Sima Yi, who was then then serving as the Grand Commandant under the Wei government. Although his strength is very good, it was to protect the homeland and donate to many people. Deng Ai is deliberate with his troops without being hindered, he had to bear the punishment of others and caused those ambitions so that would not be dread.
Every war has long since departed and Deng Ai accepted this service until a coup d’état, Sima Yi felt that Deng Ai was an extraordinary person, so he recruited him and promoted him to the position of a Gentleman of Writing. However, Deng Ai is promoted by Sima Yi and charged with the defense of Jiang Wei's raids on the southern border to Shu. After Sima Yi's death, Deng Ai later served under Sima Shi. Sima Shi is a new assistant to the government and has adopted the recommendations of Deng Ai, but he was appointed as the chief of Runan. Deng Ai observed a lot of impressions every time, maybe indeed abnegate the collusion of Sima Shi and diametrically rush out.
After he took office, he visited the same county elders who had favored him in the past. When the elders were already dead, they sent officials to go to sacrifices and reward their families. After Sima Shi dies, Deng Ai determined to gain significant power and Jiang Wei had the opportunity to send tens of thousands of troops to defeat Wei, Chen Tai died and was still surrounded by Jiang Wei. Deng Ai wants to be a useful warrior and never be so awkward to others, he conquered the Shu kingdom together with General Zhong Hui, Jiang Wei has would beat him back in Hanzhong. At that time, Deng Ai advised the army to pass through the Yinpin pass, but Zhong Hui remind himself for request that he was refused by them.
When Deng Ai was set out alone with his armies and had great success, Jiang Wei managed to used his behavior to harass them. For the start, Deng Ai was conquered Shu capital Chengdu and forced Emperor Liu Shan to abdicate. Deng Ai only saw a reasonable officer to discuss with the troops, as far so the things that were explained passed on them. Jiang Wei is tried to defend the kingdom of Shu after all. Meanwhile in the battle, he teamed with his remaining forces with Zhong Hui to pull against Deng Ai. Before that, however, they instructed officer Wei Guan to assassinate Deng Ai.
Jiang Wei's plan has failed at all and Deng Ai killed him and Zhong Hui. Seeking tried to behave himself is right, Deng Ai overcome on the battlefield and other armies grudgingly continued to entangle with them when he achieve a sensation. Wei Guan's soldiers fled to Deng Ai, but Wei Guan feared Deng Ai's revenge and murdered him by night and fog. Tian Xu and his soldiers intercepted Deng Ai in the west of Mianzhu and killed him along with his son Deng Zhong and Shi Zuan. After Deng Ai's death, his other sons in Luoyang were rounded up and executed, and his surviving family was exiled to the Western Regions.
Deng Ai is Wei general and served as a minister. However, after witnessing the wisdom of Sima Yi, he decided to return to the battlefield and observe the troops in the battle against Shu. He likes to look at the map, and he is cautious about changing the geography war in order to maintain accuracy. His humble and keen wit made him a valuable and trustworthy ally of the Sima family.
- He is a playable character in the Dynasty Warriors video game series.