Abu'l-Hasan Ali ibn al-Hasan (Persian: ابوالحسن علی بن حسن‎‎), better known by his laqab of Fakhr al-Dawla (Arabic: 'فخر الدولة‎‎, "Pride of the Dynasty") (died October or November 997) was the Buyid amir of Jibal (976–980, 984–997), Hamadan (984–997) and Gurgan and Tabaristan (984–997). He was the second son of Rukn al-Dawla.

Abu'l-Hasan Ali ibn al-Hasan was born in 952; he was the son of Rukn al-Dawla and a daughter of the Dailamite Firuzanid nobleman Al-Hasan ibn al-Fairuzan, who was the cousin of Makan ibn Kaki. Abu'l-Hasan received the title of "Fakhr al-Dawla" in 975.

In January of 976 Rukn al-Dawla met with his eldest son, 'Adud al-Dawla, who ruled in Fars. 'Adud al-Dawla consented to Rukn al-Dawla's request that Fakhr al-Dawla be made the ruler of Ray upon his death, while Hamadan would go to a third son, Mu'ayyad al-Dawla, in exchange for a promise that both of them would recognize him as senior amir. Only eight months later, Rukn al-Dawla died and Fakhr al-Dawla succeeded him in Ray, and shortly had his cousin Ali ibn Kama executed.

Fakhr al-Dawla's reign was shortened by his attempts to repudiate 'Adud al-Dawla's authority over him. He allied with his cousin 'Izz al-Dawla, who ruled in Baghdad and was an enemy of 'Adud al-Dawla. When the latter was defeated by 'Adud al-Dawla in 978, Fakhr al-Dawla struck up an alliance with the Ziyarid prince Qabus and asked for support from the Samanids. Mu'ayyad al-Dawla, an ally of 'Adud al-Dawla, was entrusted by the senior amir to eradicate Fakhr al-Dawla's power. He marched into Fakhr al-Dawla's territory, forcing the latter to flee to the Ziyarids. Mu'ayyad al-Dawla continued his campaign, however, causing both Fakhr al-Dawla and Qabus to seek refuge in Samanid Khurasan. Mu'ayyad al-Dawla then ruled Ray as 'Adud al-Dawla's subordinate.

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