Colbert, who hosts The Late Show from the Ed Sullivan theater, impersonated the legendary host when introducing BTS.
The segment was presented in black and white and featured screaming audience members wearing 1960s-era clothing and wigs.
BTS, which consists of members J-Hope, Jungkook, Jimin, Suga, Jin and RM, sat down for an interview with Colbert where they individually introduced themselves and praised their dedicated fans.
The group, when asked which Beatles song was their favorite, started to perform a harmonized version of "Hey Jude."
BTS made headlines on Wednesday when they kicked off Good Morning America's summer concert series with a high-energy performance at Central Park in New York City.
BTS released their latest EP titled Map of the Soul: Persona in April. The group recently took home the awards for Top Social Artist and Top Duo/Group at the 2019 Billboard Music Awards.