The 1975 New South Wales Rugby Football League premiership was the 68th season of Sydney's professional rugby league football competition, Australia's first. Twelve teams, including six of 1908's foundation clubs and another six from across Sydney competed for the J. J. Giltinan Shield during the season, which culminated in a grand final match for the WD & HO Wills Cup between the Eastern Suburbs and St. George clubs. NSWRFL teams also competed for the 1975 Amco Cup.