Brendan O'Hagan (born 30 October 1998) is an Ireland international rugby league footballer who plays as a and for The Entrance Tigers in the Central Coast League.
O'Hagan was born in Gosford, New South Wales, Australia. He is of Irish descent.
O'Hagan played for the Mount Pritchard Mounties in the NSW Cup.
He joined York City Knights ahead of the 2021 season. During his time with the club he made 27 appearances, scored 12 tries and one field goal.
In January 2023, the York granted O'Hagan a release from his contract to return to Australia where he joined the Wynnum Manly Seagulls for the 2023 Queensland Cup season. O'Hagan made 15 appearances for the Seagulls. He was released at the end of his contract and signed for The Entrance Tigers in the Newcastle Rugby League.
In 2022 O'Hagan was named in the Ireland squad for the 2021 Rugby League World Cup, making his debut, and scoring a try, against on 16 October 2022.