Oleksandr Stanislavovych Syrskyi (Ukrainian: Олександр Станіславович Сирський; born 26 July 1965) is a Ukrainian military officer holding the rank of four-star general who has served as the commander-in-chief of the Armed Forces of Ukraine since 8 February 2024. Previously, he was the commander of the Ukrainian Ground Forces from 2019 to 2024, and the commander of the Joint Forces Operation from May to August 2019.

During the Russian invasion of Ukraine, Syrskyi commanded the defence of Kyiv. In September 2022, he commanded the Kharkiv counteroffensive. He then led the defense of Bakhmut into 2023.

Syrskyi was born on 26 July 1965 in the village of Novinki [ru], Vladimir Oblast, Russian SFSR, into a military family, the son of Lyudmila and Stanislav Syrskyi. As of 2023, his parents and brother live in Russia. In 1980, when Syrskyi was 15, his father was transferred to serve in the Soviet Armed Forces in Kharkiv, Ukrainian SSR. Syrskyi graduated from high school in Kharkiv and entered the Moscow Higher Military Command School, the Soviet Union’s most prestigious military academy. After his graduation in 1986, Syrskyi joined the Soviet Artillery Corps. He initially served in a self-propelled artillery unit equipped with the 152 mm 2S5 Giatsint-S and 203 mm 2S7 Pion self propelled howitzers, including in units earmarked to fire nuclear shells. He later served in Rocket Artillery units fielding the BM-27 Uragan MBRL. He served in Afghanistan, the Tajik SSR, and Czechoslovakia until the dissolution of the Soviet Union in 1991.

In 1993, following the dissolution of the USSR, Syrskyi's military unit in Chuhuiv was placed under Ukrainian command, and at the age of 28 he was promoted to the position of battalion commander (equivalent to the rank of lieutenant-colonel) in the 6th Division of the National Guard of Ukraine; he later became a regiment commander in that division. In 1996, Syrskyi graduated from the National Defense University of Ukraine, and in 2005 he received a graduate degree from the same university.

In the early 2000s, Syrskyi was promoted to commander of the 72nd Mechanized Brigade, based in Bila Tserkva and promoted to the rank of major-general. He was appointed as a Chief of Staff – first deputy of the United Operative Commander of the Ukrainian Armed Forces in 2007. In 2009, Syrskyi was promoted to major general by decree of President Viktor Yushchenko. In 2011-2012 he was first deputy of the Main Directorate of military collaboration and peace-keeping operations. In 2013 he was stationed at NATO's headquarters in Brussels.

At the beginning of the war in Eastern Ukraine, he was the chief of staff of anti-terrorist operations. In particular, he was one of the chief commanders of the anti-terrorist operation forces during the battle of Debaltseve. In the winter of 2015, he went to the city with the Chief of the General Staff of the Armed Forces of Ukraine Viktor Muzhenko. He led the battles in Vuhlehirsk, the village of Ridkodub and an unsuccessful attempt to recapture Lohvynove. He also coordinated the withdrawal of the Ukrainian military from Debaltseve. Under his leadership, possible routes of crossing the Karapulka River were blown up.

Oleksandr Syrskyi was awarded the Order of Bohdan Khmelnytsky III degree and later received the rank of lieutenant-general due to his achievement during the battle of Debaltseve. In 2016, he headed the Joint Operational Headquarters of the Armed Forces of Ukraine, which coordinates the operational actions of various Ukrainian security forces in the Donbas. In 2017, he was the commander of the entire Anti-Terrorist Operation in eastern Ukraine. It was later replaced by the Joint Forces Operation.

From 6 May to 5 August 2019 he was the commander of the Joint Operational Staff of the Armed Forces of Ukraine.