Akizuki Tanesada was an heir to the Hyūga-Takanabe domain, or han.  His father was Nagano Kaneyoshi and his mother the daughter of Akizuki Tanezane.  His formal wife was Ochō, the daughter of Akizuki Tanenaga.  His eldest son was Akizuki Taneharu.

Akizuki Tanenaga, the first head of the Takanabe clan, did not have a son, so, in 1607, he adopted his nephew, Tanesada, as his son-in-law and designated heir.  However, Tanesada was of frail health, so, in 1613, he was removed from the line of succession and his eldest son, Taneharu, became the designated successor to the clan.