Jack Nies (pronounced niece) (born November 11, 1937) is a retired National Basketball Association (NBA) referee.
Wearing #35 throughout his 31-year career, only Dick Bavetta and Joey Crawford have had more years of NBA officiating experience than Nies.
Nies officiated 2,046 regular-season games throughout his career, making him the sixth referee to do so.
In addition, Nies oversaw 150 playoff games, 10 NBA Finals games, two NBA All-Star Games (1996 and 2005), and the 1987 Legends Classic.
Internationally, he was part of the referee crew that oversaw the 1994 Mexico Challenge and the 1997 McDonald's Championship; 2007 Istanbul, Turkey; Malaga and Madrid Spain—NBA Preseason Games
Nies retired from the NBA following the 2008–09 season.