Tommy O'Brien (born 28 May 1998) is an Irish professional rugby union plays centre or wing for United Rugby Championship club Leinster and Ireland national team.
O'Brien attended Blackrock College and played in the Leinster Schools Rugby Senior Cup for the school, as well being a Leinster Schools 110-metre hurdles champion.
O'Brien made his senior competitive debut for Leinster in their round 8 2019âÂÂ20 Pro14 interprovincial clash against Ulster on 20 December 2019, with O'Brien starting at 13 for Leinster and playing 70 minutes in their 54âÂÂ42 win against the northern province.
O'Brien represented Ireland under-20s between 2017 and 2018, and captained the side during 2018.
In July 2025, he made his debut for the senior side scoring two tries as Ireland defeated Georgia 34âÂÂ5 in the first match of the 2025 summer tour. He scored a further two against Portugal a week later.