- Born: 1541
- Died: 1600
- Sons: Mizuno Katsushige, Mizuno Tadakiyo
- Titles: Izumi no Kami
- Distinction: Tokugawa, Oda, and Toyotomi retainer
Tadashige was the son of Mizuno Tadamasa and succeeded his brother Nobutomo when the latter was killed on charges of treason in 1576. He served in many of Tokugawa Ieyasu's battles (including Anegawa, Mikatagahara, and Takatenjin) but became a retainer of Oda Nobuo after 1582 and served on his side in the Komaki Campaign (1584). He afterwards joined Toyotomi Hideyoshi and accompanied him in the Kyushu Campaign. He was murdered in 1600, just prior to the start of the Sekigahara Campaign, by Kagai Hidemasa.
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005