It was announced in May 2014 that O'Leary would be returning to Ireland for the 2014–15 season. He signed for the provincial side Connacht, joining on a one-year deal. In his first season with the team O'Leary made four appearances in the Pro12, scoring two tries. He didn't feature in the 2014–15 Challenge Cup but featured in the team's play-off to qualify for the following season's Champions Cup. All of O'Leary's appearances for the senior team in his first year came from the bench. In August 2015, he agreed another one-year deal with Connacht.