- Died: 1532
- Sons: Miyoshi Nagayoshi, Miyoshi Yukiyasu (Jikkyû), Miyoshi (Atagi) Fuyuyasu, Miyoshi (Sogo) Kazunari
- Titles: Chikuzen no kami
- Other Names: Miyoshi Nagamoto
Motonaga was the eldest son of Miyoshi Yukinaga and originally a retainer of the Hosokawa. In 1521 he completed work on the Miyoshi stronghold in Settsu at Saki, which he named the 'Mandokoro'. He acted on behalf of Hosokawa Harumoto and Ashikaga Yoshitsuna in their bid for power and lodged them in Sakai. Motonaga and Harumoto soon grew hostile towards one another, and in 1532, with the help of the Ishiyama Hongan-Ji, Harumoto suddenly attacked Motonaga at the Kenpon-Ji in Sakai and forced him to commit suicide.
- Initial text from Sengoku Biographical Dictionary (Samurai-Archives.com) FWSeal & CEWest, 2005