Aleksander Słuszka (1580–1647) of Ostoja coat of arms was a Polish-Lithuanian Commonwealth noble and politician. Starost of Rzeczyca (Rechytsa), Homel (Gomel), Mazyr (Mozyr) and Łojów (Loyew). Castellan of Minsk (1626). Voivode of Minsk (1635), Voivode of Nowogródek (Navahrudak) (1636), Voivode of Troki (Trakai) (1642–1647). Marshal of the Lithuanian Tribunal in 1631.
Raised in a Calvinist family, in 1621 he and his wife converted to Roman Catholicism. From then on, a devout Catholic, he funded two monasteries and two churches.