In 1900, aged 22, he won his first national title when he knocked out Jack Fitzpatrick in the Antient Concert Rooms (later the Academy Cinema on Pearse Street, Dublin) to become Irish middleweight champion.

He retained that title for five years before losing to Young John L. Sullivan in 1905 in the Earlsfort Terrace Rink, Dublin.

[5] In October 1907 Roche scored a major victory, knocking out Charlie Wilson (former British heavyweight champion) in the Olympia Theatre, Dublin, which set him up for a title shot.

On St. Patrick's Day 1908, Roche fought Tommy Burns for the world heavyweight title at the Theatre Royal, Dublin, with a purse of £1,500 (split 80:20).

[9][10] Roche married Bridget Furlong in 1908 and they lived in Wexford and had five children: their sons Pierce and Seamus also had careers in boxing.