His eldest son Ii Naomune was killed in a battle at Tahara castle, and his two younger sons Ii Naomitsu and Ii Naoyoshi were killed by Imagawa Yoshimoto. However, several of Naohira's grandsons went on to play significant roles in the latter portion of the Sengoku period. Naohira also had a daughter, who was adopted by Imagawa Yoshimoto, and who gave birth to Lady Tsukiyama (who would later become the first wife of Tokugawa Ieyasu).
- Asao Naohiro (ed.), Fudai daimyô Ii ke no girei, Hikone Castle Museum (2004), 12.