The flag of South Korea, also known as the Taegukgi (also spelled as Taegeukgi, lit. 'Taegeuk flag'), has three parts: a white rectangular background, a red and blue Taegeuk in its center, and four black trigrams, one in each corner. Flags similar to the current Taegeukgi were used as the national flag of Korea by the Joseon dynasty, the Korean Empire, and the Korean government-in-exile during Japanese rule. South Korea adopted the Taegukgi as its national flag when it gained independence from Japan on 15 August 1948.

The flag's field is white, a traditional color in Korean culture. White was common in the daily attire of 19th-century Koreans, and it still appears in contemporary versions of traditional Korean garments, such as the hanbok. The color represents peace and purity.

The circle in the flag's center symbolizes balance in the universe. The red half represents positive cosmic forces, and the blue half represents the opposing negative cosmic forces.

Together, the trigrams represent movement and harmony as fundamental principles. Each trigram (hangeul: 괘 [gwae]; hanja: 卦) represents one of the four classical elements (water, earth, fire and air).