Denys Hennadiyovych Prokopenko (born 27 June 1991) is a Ukrainian Brigadier general in the National Guard of Ukraine and commander of the 1st Corps of the Ukrainian National Guard "Azov", as well as a prominent participant of the Russo-Ukrainian War, and former commander of the 12th Special Forces Brigade "Azov".

Prokopenko joined the Azov Battalion in July 2014 to fight in the Donbas war against Pro-Russian separatists. After Azov's founder and leader Andriy Biletsky left the unit to focus on politics, Prokopenko eventually arose to the leadership of the Azov Regiment in 2017 and was promoted to the rank of major, becoming the youngest commander in the Ukrainian military. In response to the full-scale Russian invasion of Ukraine in 2022, Prokopenko rose as a leader defending Mariupol from the Russian siege, and commanded the Mariupol garrison. For his leadership role on the frontlines of the war, he was awarded the title Hero of Ukraine in March 2022. In July 2023 Prokopenko returned to Ukraine in a prisoner exchange and in August he took command of Azov once again. In April 2025 he was promoted to Colonel and became commander of the 1st Azov Corps, a newly created corps formation with four brigades. In February 2026 Prokopenko was promoted to Brigadier general.

Prokopenko is also known as Redis, an old football ultra nickname that became his military call sign. His subordinates are reported to address him informally as "Brother Redis" or "Comrade Redis".

Since childhood, he has been involved in sports, notably football and martial arts. Together with his wife, he also been involved in skiing, claiming a personal record is 91 km/h. Before the start of the Russian-Ukrainian war, he was an active fan and ultra-supporter of the Kyiv football club Dynamo. He was a member of the far-right White Boys Club football fan (known as "ultras") organization of the football club Dynamo Kyiv.

He graduated from the Department of Germanic Philology at Kyiv National Linguistic University, where he earned a degree with a specialty in teaching English.

In 2020, he entered the National Defense University of Ukraine (Command and Staff Institute for the Use of Troops), specializing in Combat Use and Control of Military Units of Mechanized and Tank Troops.

From 11 July 2014 Prokopenko has participated in the war in Donbas, initially as an enlisted soldier and then as leader of a platoon and a company. In a July 2016 interview he described improvements in the military capabilities of his troops: “Although we lost a lot of experienced guys from the old squad, we've grown in quantity and quality. Discipline and combat efficiency have improved. We used to run with bobby pistols and sawn-off shots; now we have opportunities to work with tactical tank groups, armored vehicles, artillery support. We gradually developed our military science doctrine—starting with practice, not theory. In the course of training and fighting, the lads mastered tactics and small arms proficiency. Many new possibilities opened for us: we can operate independently on the frontlines, free of other subunits that constantly let us down in combat operations.” In September 2017 he was promoted to the rank of major and given control of the Azov Regiment, becoming the youngest commander in the Armed Forces of Ukraine.

Following the full-scale Russian invasion of Ukraine, Prokopenko recorded a video message on 7 March 2022 in which he called for closing the skies over Ukraine to help avert humanitarian collapse in Mariupol, since “the enemy is breaking the rules of the war by shelling the civilian people and destroying the infrastructure of the city; the enemy is subjecting Mariupol to another genocide.”