| Clubname: | Fenerbahçe U21 |
| Fullname: | Fenerbahçe S.K. U21 |
| Nickname: | |
| Short Name: | FB |
| Ground: | Lefter Küçükandonyadis Training Facilities |
| Capacity: | 2,000 |
| Chrtitle: | Chairman |
| Chairman: | Ali Koç |
| Mgrtitle: | Manager |
| Manager: | Şenol Çorlu |
| League: | U21 Ligi |
| Website: | https://www.fenerbahce.org/ |
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Fenerbahçe S.K. U21, commonly known as Fenerbahçe S.K. B is a football club based in Istanbul, Turkey. It is the reserve team of Fenerbahçe S.K. and the club play in the U21 Ligi.
| Competition | scope=col | Titles | scope=col | Seasons/Years |
|---|---|---|---|---|
| Domestic | ||||
| scope=col | U21 Ligi | 5 | 1997–98, 1998–99, 2000–01, 2013–14, 2016–17 | |
| scope=col | U21 Super Cup | 1 | 2017 | |
| Defunct | ||||
| scope=col | Istanbul Youth Championship | 18 | 1913, 1914, 1924, 1927, 1933, 1934, 1935, 1936, 1946, 1949, 1954, 1955, 1956, 1963, 1970, 1975, 2000, 2006 | |
| scope=col | Istanbul Football League B | 12 | 1916–17, 1920–21, 1922–23, 1930–31, 1932–33, 1934–35, 1935–36, 1936–37, 1938–39, 1940–41, 1944–45, 1946–42 |