- Died: 1566
- Childhood Name: Kouchiyooumaru
- Japanese: 足利 藤氏
Fujiuji was the son of Ashikaga Haruuji (d.1560), his mother being the daughter of Yanada Takasuke. He received the "Fuji" in his name from the 13th Shogun, Ashikaga Yoshifuji (later known as Ashikaga Yoshiteru.) In 1561, he was installed as Koga Kubo by Uesugi Kenshin. Due to ongoing conflict between the Hojo and the Uesugi, Fujiuji fled back and forth between Kazusa and Koga until 1562, when Hojo Ujiyasu invaded Koga, and captured him. He was held variously in Sagami and Izu until he was executed by Ujiyasu in 1566.