Harold Alexander Cahill (9 June 1930 – 18 September 2009), also known as Harry Cahill, was a Great Britain and Ireland men's field hockey international goalkeeper. He represented Great Britain at the 1960, 1964 and 1968 Summer Olympics. Between 1953 and 1973 he made 72 senior appearances for Ireland. He also represented Ireland at the 1970 Men's EuroHockey Nations Championship. In 1961 Cahill won an Irish Senior Cup winners medal with Belfast YMCA. In 2006 he was inducted into the inaugural Irish Hockey Association Hall of Fame. He died on 18 September 2009 while on holiday in France.