Igor Dmitrievich Sergun (Russian: Игорь Дмитриевич Сергун, IPA: [ˈiɡərʲ ˈdmʲitrʲɪjɪvʲɪtɕ sʲɪrˈɡun]; 28 March 1957 – 3 January 2016) was a Russian military officer who was a director of GRU, Russia's military intelligence service, from 2011 until his death in January 2016. He was promoted to colonel general on 21 February 2015.

Igor Sergun was born on 28 March 1957 in Podolsk, Moscow Oblast. He completed the Moscow Suvorov Military School and the Moscow Higher Military Command School. He was in active military service from 1973, in the GRU from 1984.

There is no information in the public domain on him participating in the Soviet military campaign in Afghanistan in the 1980s, or in the Chechen Wars in the 1990s, or any other actual combat.

In 1998, Sergun had a rank of colonel and served as military attaché in Tirana, Albania.

On 26 December 2011, Sergun was appointed Director of GRU, which had in 2010 received a new official name, the Main Directorate of the General Staff. He also became Deputy Chief of the General Staff of the Armed Forces of the Russian Federation.

He was promoted to Lieutenant-General by a presidential decree on 31 August 2012 and Colonel General on 21 February 2015.

In 2014, Sergun was put on the sanction lists of the EU and the U.S. as a person ″responsible for the activity of GRU officers in Eastern Ukraine″.

He was last spotted by media at Bocharov Ruchey, as one of the Russian delegation for negotiations with King Abdullah II of Jordan, on 24 November 2015.