Elko County is a county located in the U.S. state of Nevada. As of the 2010 census, the population was 48,818. Its county seat is Elko. The county was established on March 5, 1869, from Lander County. Elko County is the fourth-largest county in the contiguous United States, ranking lower when the boroughs of Alaska are included.
Elko County is part of the Elko micropolitan area.