Hosokawa Takakuni (細川 高国, 1484 – July 17, 1531) was the most powerful military commander in the Muromachi period under Ashikaga Yoshiharu, the twelfth shogun. His father was Hosokawa Masaharu, who was the branch of the Hosokawa clan. In 1507, Hosokawa Masamoto was killed by the foster son, Hosokawa Sumiyuki who was cut off by Masamoto. Takakuni supported Hosokawa Sumimoto and got the credit for putting down Sumiyuki. Because of that, he came to participate in the Muromachi shogunate in depth.