- Born: 1573
- Died: 1593
- Other names: Mataichirô
- Distinction: Shimazu retainer
- Japanese: 島津久保 (Shimazu Hisayasu)
Shimazu Hisayasu was the eldest son of Shimazu Yoshihiro. Since his uncle, Shimazu Yoshihisa, had no heir, he adopted Hisayasu to be his heir. After the Shimazu clan submitted to the authority of Toyotomi Hideyoshi in 1587, Hideyoshi granted Morokata district in Hyûga province to Hisayasu as his fief, but then also took Hisayasu to Kyoto as a hostage. There, he was married to Yoshihisa's daughter Shimazu Kameju.