JJ or jj may refer to:
Juan José Rendón Delgado (born 1964 in Caracas, Venezuela), known professionally as JJ Rendon, is a Latin American political consultant, psychologist and political activist.
JJCC (pronounced J-J-C-C, Hangul: 제이제이씨씨) is a six-member South Korean hip-hop boy group formed under the management of Jackie Chan Group Korea.
James Edward "JJ" Hickson, Jr. (born September 4, 1988) is an American professional basketball player, currently for Champville SC in Lebanon.
Jyrki Juhani Järvilehto (Finnish pronunciation: [ˈjyrki ˈjærvilehto]; born 31 January 1966 in Espoo), better known as "JJ Lehto", is a Finnish racing driver.
John Joseph Feild (born 1978), known professionally as JJ Feild, is a British-American actor.
JJK Jyväskylä (JJK) is a Finnish football club, based in Jyväskylä. It currently plays in the Finnish second highest league Ykkönen.
JJ Project (Korean: 제이제이 프로젝트) is a South Korean pop duo, consisting of JB and Jinyoung. They were formed by JYP Entertainment and released their first single "Bounce" in May 2012. They redebuted as a part of Got7 in January 2014.
JJB Sports plc (stylized as JJb sports) was a British sports retailer. On 24 September 2012, shares in JJB Sports were suspended, and the firm called in administrators.
John-James Chalmers (born 1987) is a television presenter and Invictus Games medallist. Chalmers served in Helmand, Afghanistan as a Royal Marine with 42 Commando.