Ryonen (1646 - October 29, 1711) was a Buddhist nun of the Obaku Sect who lived from the early Edo period to the mid-Edo period. She was a daughter of Choji KATSURAYAMA, who was a great-grandchild of Shingen TAKEDA. Her secular name was So. Her azana (adult males nickname) was Ryonen. Her imina (real personal name) was Genso. She was born in Kyoto.
After serving Tofukumonin, Chugu (second consort of the emperor) of the Emperor Gomizunoo, she married Bansui MATSUDA and had two boys and three daughters. However, she left the Matsuda family in 1672 and served Takagimi, a grandchild of Chugu Tofukumonin. After the death of Takagimi, she studied under Princess Richu in Hokyo-ji Temple in Kyoto, daughter of Emperor Gomizunoo, and entered into the priesthood. She then went to Edo and asked Michiyasu HAKUO, a Zen monk of the Obaku Sect, to take her in as his disciple, but her request was refused because of her good looks and only eventually was she allowed to become his disciple after burning her face. In 1693, she built Taiun-ji Temple in Kamiochiai village, Musashi Province (now Shinjuku-ku Ward, Tokyo Prefecture) with having HAKUO as kaizan (a founder of temple as the first chief priest) and called herself second founder.