Ryôku was a member of a branch of the Uruku dunchi Ba family started by Ba Urasoe ueekata Ryôsen. This branch held the position of sô-jitô of Ôzato magiri, and included nine other members of the Sanshikan, including Yonabaru Ryôkyô and Yonabaru Ryôketsu.
Ryôku led a tribute mission to Beijing in 1762 and traveled to Kagoshima in 1765 to report the success of that mission. He was appointed to the Sanshikan in 1769 and served in that position until his retirement in 1796.
Known for his virtue and for his numerous ryûka poems, towards the end of his life he came to be known as kunshi ueekata, or, roughly, "the gentleman official." He was also known for his talent in writing Japanese-language prose.
Yonabaru Ryôku died in 1797 at the age of 80.
- Explanatory plaque at Yonabaru's birthplace, Naha-shi Shuri Gibo-chô 3-14.