Yonabaru Ueekata Ryōku (与那原 親方 良矩, 29 June 1718 – 23 October 1797), also known by his Chinese style name Ba Kokuki (馬 国器), was a bureaucrat of the Ryukyu Kingdom. He was the ninth head of an aristocrat family, (馬氏与那原殿内). He was dispatched to China to pay tribute together with (梁 煌) in 1762, and was sent to Satsuma to report this in 1665. Yonabaru was skilled at ryūka poetry. He was designated a member of the (沖縄三十六歌仙, Okinawa Sanjūrokkasen).