Nizhneilimsky District is an administrative district, one of the thirty-three in Irkutsk Oblast, Russia. Municipally, it is incorporated as Nizhneilimsky Municipal District. The area of the district is 36,823 square kilometers (14,217 sq mi). Its administrative center is the town of Zheleznogorsk-Ilimsky. Population: 55,096 (2010 census); 63,727 ; 77,291 (1989 Soviet census).