One of the Noh flute schools. The founder of the school was Nakamura Shichirōzaemon （died in 1539）, who was a disciple of the master Higaimoto Hikobee （died in 1527 ）, so the school was also known as the Nakamura-ryū. The Nakamura family took the surname Issō from Nakamura Hachirōemon III. In the Edo period, the school mainly belonged to the Hōshō school company. The sound of the flute is powerful and straightforward, with few ornamental notes. It is said that there are many musical differences compared to the two flute schools of Morita-ryū and Fujita-ryū. The school retained by the Sendai clan, Hiraiwa-ryū, which ceased to exist after the Meiji era, was believed to be in a family tree close to the Issō-ryū. The current performers are mainly based in Tokyo.