The Cathedral of the Assumption of Mary, also known as the "Royal and Renowned Basilica Cathedral of the Assumption of the Blessed Virgin Mary", is a significantly important and historic landmark in León, Nicaragua. The cathedral was awarded World Heritage Site status with the United Nations Educational, Scientific and Cultural Organization (UNESCO). The site's nomination is Nicaragua's third cultural landmark, following the ruins of León Viejo and El Güegüense.

León is the second largest city in Nicaragua, after Managua. Founded by the Spanish as Santiago de los Caballeros de León, it is the capital and largest city of León Department. As of 2022, the municipality of León has an estimated population of 213,718.