From 1993 to 1998, he studied at the Kyiv National Economic University. In 2008, he co-founded Krai Kinema. In 2008, he made educational short film "A Wonderful Day for a Banana Fish", and in 2009, "Horn of the Bull". In 2012, he debuted his first feature film, Gamer, at the Rotterdam International Film Festival. "Gamer is a film about fellow gamers. The protagonist of the film spends most of his time playing the computer game Quake, which is very detrimental to his studies in technical school. His mother thinks he is good for nothing and no better than his father who left the family. The film had a budget of $20,000 and was played by real gamers. Also in 2012, the film won the Guild of Historians of Cinema and Film Critics Prize at the Spirit of Fire festival in Khanty-Mansiysk. In 2013, Oleg Sentsov presented his new project, Rhinoceros, at the Odessa Film Festival. This project won a prize of 25 thousand hryvnias. Rhinoceros is a guy whose father constantly drank and then was in prison, his mother was always fighting, his older brother died in the war, his sister also had a bad life, so it is not surprising that the boy, who grew up in such a family, when he grew up - turned into a rhinoceros. The main events of the feature film take place in the early 1990s in a gangland setting. Work on this project was halted by Oleg's active participation in the protests. In February 2022, the popular streaming service Netflix acquired the rights to screen Rhino.

Sentsov has been an active participant in the Euromaidan since it began. In particular, he joins AutoMaidan activists. And after the start of Russia's temporary annexation of Crimea, he frequently travelled to his native Simferopol, where he tried to organise rallies "For One Country" and also provided food and supplies to the Ukrainian military who were stationed in Crimea.

On 10 May 2014, he was detained in Simferopol by Russian security forces and sentenced on 25 August 2015 on terrorism charges to 20 years' imprisonment to be served in a high-security colony.

In June 2015, Kiev-based publishing house Laurus published a book of Oleg Sentsov's short stories written before his imprisonment in Russia. The collection includes eight stories in Russian: "Autobiography", "Dog", "Childhood"[11], "Hospital", "School", "Testament", "Grandmother", and "Makary". The publication was initiated by director Oles Sanin and producer Anna Palenchuk. Sentsov's family will receive half of the profits from the sale of the book. After his imprisonment, Oleg Sentsov also started writing a novel.

In 2017, Aleksandr Mimruk's book Oleg Sentsov was published, which consists of the memories of people who know Oleg well, excerpts from his books and film scripts, as well as extracts from the interrogation of witnesses in his case.

In 2019, the first Ukrainian translation of Oleg Sentsov's works Life, published thanks to the initiative of Ukrainian producer Anna Palenchuk, a joint effort of Old Lion Publishing and Ukrainian PEN, has been announced. The prose was translated into Ukrainian by Sergiy Osoka. In the same year, the book is published in German, English and Polish.

On 7 September 2019 it was returned as part of an exchange of Russian criminals from Ukraine for Ukrainian prisoners of war from the Russian Federation.

Joined the ranks of the Territorial Defence of Ukraine at the start of Russia's invasion of Ukraine.