Ōno Harunaga (大野 治長, 1569 – 4 June 1615) was a general under Toyotomi Hideyori, and fought in the Siege of Osaka in 1615. He became lord of Osaka castle after the Battle of Sekigahara. Ono led forces against those of Wakayama Castle in the Battle of Kashii, also the Battle of Shigino, and the Battle of Tennoji, where he was killed in action. He held the rank at court of Junior Fifth Rank. Harunaga had a fiefdom of 15,000 koku.