- Birth: 1492?
- Death: 1554
- Dinstiction: Amako retainer
- Title: Gyoubu Shosuke (刑部少輔), Kii no kami
- Children: Amako Sanehisa, Amako Toyohisa, and Amako Takahisa
- Japanese: 尼子 国久 (Amako Kunihisa)
Kunihisa was a son of Amako Tsunehisa and was known in his youth as Magoshirô [孫四郎]. He was a principle Amako general while Tsunehisa was alive, leading a force that came to be nicknamed the 'Shingu [新宮] army' (after the valley to the north-east of Gassan-Toda where Kunihisa's mansion was located). He also acted as the guardian for Amako Haruhisa (Akihisa) after the latter's father, Masahisa, was killed in 1518. He fought under his father in campaigns in Aki and Bingo provinces during the 1520's and alongside Amako Haruhisa at the Siege of Koriyama Castle in 1540. He defeated a Môri army in 1544 but lost his second son, Toyohisa, at the hard-fought Battle of Hashizugawa [橋津川] in 1546 fighting against Takeda Kuninobu of Inaba province.
Despite his many services, Kunihisa came to be distrusted by Haruhisa, his nephew and the daimyô after Tsunehisa's death. For reasons unclear, Kunihisa was executed at Gassan-Toda by Haruhisa on the suspicion of treason on 25 November 1554 (Tembun 23 11/1), along with his eldest son Sanehisa and two grandsons, as well as a number of his associates. His third son Takahisa commited suicide the next day. His death is often represented as a contributing factor in the eventual fall of the Amako, although modern thinking is that Haruhisa purged the Shingu faction as a way of cementing his personal control of the clan. One reason typically given for Haruhisa's hostility towards Kunihisa and the Shingu faction is that they comported themselves with increasing arrogance as their fame from their war service grew.