Oscar Aga (born 6 January 2001) is a Norwegian footballer who plays as a forward for Fredrikstad FK in the Norwegian First Division on loan from Rosenborg.
Coming through the youth ranks of Lyn and Stabæk, he made his Eliteserien debut in April 2018 against Brann. He scored his first goals in the 2019 Norwegian Football Cup, 5 goals in 3 matches. He was loaned out to Grorud at the closing of the summer 2019 transfer window. In 2021 Oscar Aga made the move to the swedish club IF Elfsborg and signed a contract that extends to 2025.
6 March 2023, Aga signed for Rosenborg on a deal until the end of 2026.
26 July 2023, Aga signed a loan deal for Fredrikstad FK on a deal until the end of the 2023 Season