Yalçın Küçük (born 1938) is a Turkish socialist writer, philosopher, economist, historian and media pundit, recognized for his historical studies on the late-Ottoman and Republican periods in the history of Turkey and Soviet economic development from a Marxist perspective and also his interest in crypto-Judaism in Turkey (Sabbateanism) and criticism of the Justice and Development Party. He was detained for 682 days in relation to the Odatv case of the Ergenekon trials (released in December 2012). In August 2013 he was sentenced to 22 years and six months, later to be released on 12/12/13.
Küçük was born in Iskenderun. His father's ancestry is Turkoman while his mother's is Caucasian. He went to the Kabataş High School, followed by Ankara University. He graduated in 1960 with a degree in political science.
His first job was in the State Planning Board, where he eventually oversaw the Long Term Planning department. In 1966 he found a position at the Middle East Technical University. He was fired after the 1971 coup. Before the coup he wrote calling for a "Socialist Revolution" and a socialist administration in Turkey in the leftist publications Yön, Emek, Ant. He is also well known for his bitter criticisms of another strategy called "National Democratic Revolution" (Turkish: Milli Demokratik Devrim).
In 1973, he became a reserve officer at the Polatlı Artillery school (military service is compulsory in Turkey). Afterward he ran the economy department of the establishment newspaper, Cumhuriyet. He also ran the economy bulletin of the Anka news agency.