Omiya Ardija (大宮アルディージャ Ōmiya Arudīja) is a professional association football club which play in the J1 League, and are based in Ōmiya in Saitama, Japan. Its "hometown" as designated by the league is the whole of Saitama city, which is shared with neighbours Urawa Red Diamonds. Omiya currently compete in the J1 League following an immediate promotion in 2015 after being relegated in 2014. They competed in J1 2005 and continued to remain in J1 between 2005 and 2014, following promotion from J2 in 2004 as the second placed team.
Their home field is Nack5 Stadium Ōmiya (Nack5スタジアム大宮 Nakku-faibu Sutajiamu Ōmiya): Ōmiya Park Soccer Stadium by the naming rights.