The national flag of the Democratic People's Republic of Korea (North Korea) consists of a wide horizontal red stripe bordered above and below by a thin white stripe and a broad blue stripe. The red stripe is charged near the hoist with a five-pointed red star inside a white disc. The design of the flag is defined in the North Korean constitution and regulations regarding the use and manufacture of the flag are outlined in the country's national flag law.
The flag was officially adopted on 8 September 1948, with the passing of North Korea's first constitution by the 1st Supreme People's Assembly. The North Korean government credits Kim Il Sung, the country's founder and first leader, with designing the flag; however, North Korean artist Kim Chu-gyong was previously recognised as its designer. Pak Il, a Soviet-Korean interpreter, claimed that it was designed by the government of the Soviet Union, and his account was corroborated by another Soviet-Korean, Chŏng Sangjin.
The display of the North Korean flag is banned in South Korea by the National Security Act, but exceptions have been made for film and television productions, as well as sports competitions.
In North Korea, the flag is known by various names, including the "Blue and Red Flag of the Republic", the "Blue and Red National Flag", the "Red-Blue Five-Pointed Star Flag", and the "Flag of the Republic". In South Korea, it is known as the "Flag of the People's Republic" or pejoratively as the "Flag of the Northern Puppet".
The design of the flag was defined in Chapter VII, Article 170 of the Socialist Constitution of the Democratic People's Republic of Korea, 1948 (2014 revision). It stated:
The national flag of the Democratic People's Republic of Korea consists of a central red panel, bordered both above and below by a narrow white stripe and a broad blue stripe. The central red panel bears a five-pointed red star within a white circle near the hoist. The ratio of the width to the length is 1:2.
The article was retained from the country's provisional constitution, which was drafted in late 1947 and adopted at a special session of the People's Assembly of North Korea in February 1948. During the session, assembly chairman Kim Tu-bong read the article describing the national flag (originally Article 100) and asked for opinions from delegates. Representative An Mong-yong expressed his concerns that the flag would fold easily when hoisted because of its length, and proposed changing the width-to-length ratio of the flag from 1:2 to 2:3. An's proposal was dismissed by Kim Tu-bong, who assured An that the existing dimensions would not be a problem.
On 23 March 2026, a new amendment was ratified that changed the flag's proportions from 1:2 to 1:1.65 (20:33 as an integral number). The design of the flag is now defined in Chapter VII, Article 166. It states:
The national flag of the Democratic People’s Republic of Korea has a wide red band in the center, bordered above and below by narrow white bands, followed by blue bands at the top and bottom.
Near the hoist side of the red band is a white circle containing a red five‑pointed star.
The ratio of the flag’s width to length is 1:1.65.
Different sources give conflicting explanations of the flag's symbolism. According to an article published on 8 August 2013 in the Rodong Sinmun, the official newspaper of the ruling Workers' Party of Korea, Kim Il Sung gave the following significance to the flag's elements after designing it:
The red colour of the flag symbolises the anti-Japanese fervour, the red blood shed by the Korean patriots and the invincible might of our people firmly united to support the Republic. The white colour symbolises the one bloodline, one land, one language, one culture of our monoethnic country, which lived in purity. And blue stands for the gallant visage of our people, symbolising the spirit of the Korean people fighting for world peace and progress.
Pak Il, a Soviet-Korean interpreter who claimed to have translated from Russian the original flag designs proposed by the Soviet government, also claimed that the flag was initially intended to be hoisted vertically, and gave the following as the original explanation of the flag's symbolism:
The red stripe was to symbolise the land of the new Korea, illuminated by the red star of communism. The blue stripes surrounding the flag were to symbolise the seas surrounding the Korean peninsula [the Yellow Sea and the Sea of Japan].
The US Central Intelligence Agency's World Factbook meanwhile states that the colours of the flag – red, white, and blue – are considered national colours and symbolise, respectively: revolutionary traditions; purity, strength, and dignity; and sovereignty, peace, and friendship. It also states that the red star is a national symbol and represents socialism.
The North Korean government has specified sizes, colours, and manufacturing parameters in which the flag is to be made. They are detailed in Appendix I of the National Flag Law of the Democratic People's Republic of Korea, 1992 (2012 revision). The width-to-length ratio of the flag was 1:2. The flag is divided into six vertical sections, with the top and bottom sixths being blue stripes. The middle four-sixths further divide into 24 sections, with the top and bottom twenty-fourths being white stripes, and the other twenty-two twenty-fourths being red. The center of the red star (and of the white disc that surrounds it) is at half the flag's height and one-third of its length. The diameter of the white disc is two-thirds the combined height of the red and white stripes. The imaginary disc described by the points of the red star has a diameter equal to half the height of the white stripe from the white disc's diameter. The points of the red star do not touch the circumference of the white disc.
The aspect ratio of the flag is amended in the Constitution of the Democratic People's Republic of Korea, March 2026 revision.