- Born: 1514
- Died: 1583
- Sons: Ogasawara Sadayoshi, Ogasawara Nagataka, Ogasawara Sadatsugu
- Titles: Sama no suke, Daizen dayu
- Distinction: Shinano warlord
Nagatoki was the ruler of the Fukashi area of north-central Shinano and allied with other Shinano daimyô in an effort to stop the expansion of the Takeda. In 1541 he allied with the Suwa and advanced into Kai province, where he was defeated by Takeda Shingen at Nirasaki. He suffered defeat again, along with Murakami, Suwa, and Kiso, at the Battle of Sezawa in 1542. After meeting further defeats at Shingen's hands, notably at Shiojiritoge (1548) and Uenohara (1552), and suffering the loss of Fukashi castle (1550), Nagatoki sought refuge (along with Murakami Yoshikiyo) in Echigo. While Murakami continued to fight the Takeda, Nagatoki retired to teach archery and horsemanship. He was murdered under mysterious circumstances many years later.
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005