Sunnybank Rugby Union Club was founded in 1969 as a Junior Rugby Union club, in the southern Brisbane suburb of Sunnybank. As a Junior Rugby club, it was founded on the principle that any child, no matter how good or bad a Rugby player they were, would get to play a game.
In its first year, Sunnybank fielded an Under 8's team and an Under 11's team. The Club played their home games at Sunnybank State High School until 1974, when the Club moved to its present home ground of Biggs Field in the nearby Brisbane suburb, Macgregor. The Sunnybank State High School colours of black, green and white and the Chinese dragon were adopted as the emblem of the new club.
In 1975, Sunnybank expanded from being solely a Junior Rugby club to being one with more Senior players, with introduction of an Under 19's side in that year. The Club then proceeded to field its first Senior team in 1979, with a team playing in the sub-districts competition. Sunnybank went from strength to strength, consistently being one of the strongest clubs in the Queensland Junior Rugby Union competition.
Sunnybank was finally promoted to First Grade status in 1989 and only had to wait until 1993 before making its first appearance in a First Grade Grand Final.