Subgroups

Since debut, SM Entertainment has created four subgroups for Super Junior. The intentions of the subgroups were part of SM Entertainment's strategy to not limit Super Junior's activities; the goal of this strategy was to show that Super Junior could accommodate different genres. Possible focuses of subgroups in the near future include a variety of genres such as rock and hip hop. As of now, none of Super Junior's previous subgroups have made comebacks in the industry (as Super Junior-Happy has thoroughly taken over the expected comeback of Super Junior-T in 2008). However, neither of the subgroups are permanently inactive and a future comeback is expected for all subgroups.

Super Junior-K.R.Y
Super Junior-K.R.Y, established in November 2006, is a trio formed by Kyuhyun, Ryeowook, and Yesung. The company discovered that these three members developed a particular persona and subsequent fan-base that was separate from the rest of the group, and how they also had similar musical qualities. They therefore grouped these three members together to perform particular songs to target a more mature audience. Being amongst the most vocally powerful members of the group, Super Junior-K.R.Y are credited to singing mournful, R&B-style ballads, a style that has proven very popular in recent years although stagnation in the style's development is causing it to lose its once fresh evocative power.

Super Junior-K.R.Y's first official performance was on November 5, 2006 on KBS's Music Bank, performing "The one I love." They have participated in the original soundtrack of the tvN drama Hyena with a total of three tracks, including the main theme. The trio also contributed tracks in two additional original soundtracks, one track in both the soundtracks of Snow Flower and Billy Jean Look at Me. Unlike Super Junior's other sub-units, Super Junior-K.R.Y has not officially released a single or album, and only participated in collaboration albums and original soundtracks. However, a comeback album is expected from K.R.Y in the future.

Super Junior-T
Super Junior-Trot (Korean: 슈퍼주니어-트로트), officially known as Super Junior-T (Korean: 슈퍼주니어-티) is the second official sub-unit of Korean boy band Super Junior, established in February 2007. They are one of the few new generation singers known to have been capitalizing trot music, the oldest form of Korean pop music. Super Junior-T contains six Super Junior members, Leeteuk (the leader), Heechul, Kang-in, Shindong, Sungmin, and Eunhyuk.

Super Junior-T has released only one single in the short span of their career before they were announced to be on hiatus in 2008. The single "Rokuko" was Korea's sixteenth best-selling record and the number one best-selling single of 2007, according to the Music Industry Association of Korea.

Super Junior-M
Super Junior-M (Korean: 슈퍼주니어-엠), often referred to as SJ-M, is the third official sub-unit of Korean boy band Super Junior established in April 2008. They are the first international music group in the Chinese music industry to have members of both Chinese and Korean descent. They are also the first group produced by Korea's CT (Culture Technology) organization and was created through a comprehensive localization strategy. Super Junior-M contains five Super Junior members, Han Geng (the leader), Donghae, Siwon, Ryeowook, Kyuhyun, and two non-Super Junior members, Henry and Zhou Mi.

Super Junior-Happy
Super Junior-Happy (Korean: 슈퍼주니어-해피), sometimes referred to as SJ-Happy or Suju-Happy (Korean: 슈주-해피), is the fourth official sub-unit of Korean boy band Super Junior established in June 2008. Super Junior-Happy contains six Super Junior members, Leeteuk (the leader), Yesung, Kang-in, Shindong, Sungmin, and Eunhyuk.