Dannah O'Brien (born 22 September 2003) is an Irish rugby union player who plays fly half for Leinster and Ireland.
From Tullow, she played Gaelic Football for Carlow at intercounty level before committing to rugby.
She plays domestic rugby for Old Belvedere, and made her Leinster Rugby debut in January 2023.
She made her debut for Ireland women's national rugby union team against Japan in 2022 at the age of 19 years-old. She signed her first professional contract with the Irish Rugby Football Union in November 2022.
She was selected in the Ireland squad to compete at the WXV1 tournament in Canada in September 2024. She made a number or successful conversions including the winning kick as they beat world champions New Zealand 29âÂÂ27 at the competition on 29 September 2024.
O'Brien was named in Ireland's side for the 2025 Six Nations Championship in March. She was named in the Irish squad for the 2025 Rugby World Cup in England.
She studied Accounting & Finance in Dublin City University.