Niu Jin ia a character in the 14th-century Chinese classic novel Romance of the Three Kingdoms by the late Luo Guanzhong, and its multiple adaptations. He is one of Cao Ren's subordinate generals. His death was controversial with many tales speculating that it could have been orchestrated by Sima Yi.
When his superiors announced his defense plan, Niu Jin called for an offensive to boost the morale of the allies and led 500 men across the Han River to meet Zhou Yu and the Southern Army. He was challenged by Ding Feng and was trapped in Wu's formation. Cao Ren heard the pain of his comrades, rode his rescue, and defeated Jiang Qin and many others with Oxford and Cao Chun. The Wei army achieved victory.
They soon heard that Gan Ning would attack Yiling, so Niu Jin and Cao Chun were secretly deployed to assist Cao Hong. Although Gan Ning occupied the city, their reinforcements separated him from his allies. When Zhou Yu personally rode to save Gan Ning, Cao Ren's army once again assisted them. In the next conflict, Cao Ren's army was fleeing and Zhou Yu rode into the city. Waiting for him is a few archers, Niu Jin tried to take away Zhou Yu's life. However, Wu forces fled and both sides suffered losses.
The physician who solved the problem of Zhou Yu's wounds instructed him to rest and alone to avoid reopening the wound. His injury has been poisoned and the disease takes time to recover. Three days later, Niu Jin marched toward their main camp, Wu forces worried about Zhou Yu's situation and did not ride a horse. The next day, Niu Jin harassed them and eventually angered Zhou Yu. The chieftain rode to meet them, pretending to be insulted by Wei army's jeers, and fell from his horse, with blood flowing in his mouth.
Cao Ren took a trick at the gate of death, ordered his troops to retaliate, and ordered Niu Jin to lead the front line of the attacking army.
- He is one of the boss characters in the Knights of Valour series.