Abu Nasr Khusrau Firuz (Persian: ابونصر خسرو فیروز, died 1058 or 1059), better known by his laqab of Al-Malik al-Rahim (Arabic: الملک الرحیم, "the merciful king") was the last Buyid amir of Iraq (October 1048 – 1055).
However, Abu Sa'd Khusrau was shortly forced back to Iraq due to increased hostility between the Turks and the Dailamite troops there.
The next year, a combined army of Arab and Kurdish tribes ravaged Ahvaz and its surrounding regions, but were later repelled by Al-Malik al-Rahim.
The Abbasid caliph, who had initially preferred the weak Buyids over the strong Seljuks despite the latter's Sunni religion, declared that Toghrül's name should be recited before that of al-Malik al-Rahim in the Friday sermons.
Barely a week had passed, however, before the citizens of Baghdad began to complain to the amir about looting committed by the Seljuk troops, asking him to expel them out of the city.