In the early years of the 20th century, football was more popular than hurling, and the club affiliated to the newly formed East Cork board in 1925. Killeagh had to wait until 1948 before it contested its first East Cork final which was in the B Grade. Nine years later Killeagh contested the East Cork Junior A hurling title for the first time but lost to a St. Catherines combination. Ten years later, in 1967, the club's wait was over when rivals Castlemartyr were defeated in the East Cork final after a replay. Further hurling titles followed in 1970 and 1971.