Shimazu Toyohisa (島津 豊久, July, 1570 – October 21, 1600) or Shimazu Tadatoyo, son of Shimazu Iehisa and nephew of Shimazu Yoshihiro, was a Japanese samurai who was a member of the Shimazu clan. He was also the castle lord in command of Sadowara Castle.He served in the Battle of Kyushu (1587) under his uncle against the Toyotomi. He fought bravely, but was ambushed off route when he charged forward. He was saved by his uncle. His wife was the daughter of Shimazu Tadanaga, cousin and karō to Shimazu Yoshihisa.