The Plain Yellow Banner (Chinese: 正黃旗; pinyin: Zhèng Huáng Qí) was one of the Eight Banners of Manchu military and society during the Later Jin and Qing dynasty of China. The Plain Yellow Banner was one of three "upper" banner armies under the direct command of the emperor himself, and one of the four "right wing" banners. The Plain Yellow Banner was the original banner commanded personally by Nurhaci. The Plain Yellow Banner and the Bordered Yellow Banner were split from each other in 1615, when the troops of the original four banner armies (Yellow, Blue, Red, and White) were divided into eight by adding a bordered variant to each banner's design. After Nurhaci's death, his son Hong Taiji became khan, and took control of both yellow banners. Later, the Shunzhi Emperor took over the Plain White Banner after the death of his regent, Dorgon, to whom it previously belonged. From that point forward, the emperor directly controlled three "upper" banners (Plain Yellow, Bordered Yellow, and Plain White), as opposed to the other five "lower" banners.

The flag of the Plain Yellow Banner eventually became the basis of the Flag of the Qing dynasty.