József Kelen (born: József Klein in Nagybocskó; January 12, 1892 – March 19, 1938 in Moscow) was a Hungarian mechanical engineer, deputy commissar of the Soviet republic of Hungary, then commissar of the Soviet republic of Hungary, brother of communist politician Ottó Korvin, cousin of Pál Hajdu, husband of the politician Jolán Kelen and the founder of the Communist Party of Hungary in Budapest.
During World War I, he worked as an engineer for the electric Tram company of Budapest.
Following the proclamation of the Soviet Republic of Hungary, he was appointed Deputy People's Commissioner for Social Production, and from April 1919 he became People's Commissioner and was inaugurated as a member of the National Economic Council and the Federal Central Administrative Committee.
He was sentenced to life imprisonment in the People's Commissar's lawsuit, and in August 1922 he moved to the Soviet Union on the occasion of the Soviet-Hungarian prisoner exchange campaign.
After returning to the Soviet Union, he was appointed head of the planning trust (Tyeploenyergoprojekt) for thermal power plants in all of Russia.