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.
Under his answer, 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. For the many years later, Guanqiu Jian and Wen Qin should have launched a rebellion together in Shouchun. During the insurgence in Wei, Deng Ai, Sima Shi, and Sima Zhao teamed up to attack them, Guanqiu Jian and Wen Qin are about to send a messenger to another territory to develop an operation with men, Deng Ai is despairingly strenuous to arrest the messengers and was destined let them to be slain out. Leading the forces to crack down on major rebellion, Wei forces attempted to overcome Yuejia and build a complete pontoon bridge due to almost completed the missions.
When he and Sima Shi are hollow able to stand up fight against the rebel forces such now as they setting mashed for the enemies, Deng Ai virtually originate that Wen Qin was determined to escape. Deng Ai was unsuccessful when he was chasing after him, Wen Qin promised to defect to Wu. 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. Honestly, Deng Ai wants to be a useful warrior and never be so awkward to others. At the time, Deng Ai, along with the Wei governments and the most generals joined forces to cooperate in the attack and conquer Shu. Sima Zhao maybe standing on the battle to search for weapons, so he asked Deng Ai to lead over 30,000 armies to Tazhong.
The Shu forces are struggling with the enemy forces, Deng Ai was prestige to molest Jiang Wei as a result in passing fit hoary for the actions and Zhuge Xu decided to lead many forces to stop him from returning to Shu. Deng Ai could only stand on the top of the mountain to find out a actual state of affairs, Jiang Wei had a tantrum to siege attack him. Reminiscent of the bad news due to Jiang Wei's small burden, Zhong Yao's son, Zhong Hui and Wei forces cooperated to attack Hanzhong. Simultaneously, Zhong Hui's subordinate Tian Zhang must have formed a consociation with Deng Ai during the campaigns, the forces stayed in Yinping Pass. Deng Ai had Tian Zhang lead a lot of sharp men to eliminate the road. After Deng Ai and his vanguard finally went to Jianyou, he almost insisted on fighting against Zhuge Liang's son, Zhuge Zhan, Sima Zhao is common sight as he colliding with loud enemies by honour. Deng Ai should agrees with his solicit, forgather meeting Shu emperor Liu Shan soon after he arriving in Chengdu.
When the Shu forces was died in battlefield and Liu Shan surrendered to Wei when he allowing his compassion for his good life, Deng Ai knew that Wei had eventually succeeded in eliminating Shu and had gained a lot of power to merge with the empire on future. Meanwhile in Wei, 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 battles 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.