Nicolae Firoiu (born 4 March 1939), commonly known as Nico Firoiu, is a Romanian former water polo player and coach. He competed in the 1960 and 1964 Summer Olympics.
After retiring as a player, he coached the national teams of Iran and Romania. In 1974, he moved permanently to West Germany. In November 1975, he became the national head coach, reforming German water polo and leading his team to a gold medal at the 1981 European Championships, as well as bronze medals at the 1982 World Championships and the 1984 Olympic Games.