Mississippi County is the easternmost county in the U.S. state of Arkansas. As of the 2020 census, the population was 40,685. There are two county seats, Blytheville and Osceola. The county was formed on November 1, 1833, and named for the Mississippi River which borders the county to the east. Mississippi County is part of the First Congressional District in Arkansas. The Mississippi County Judge is John Alan Nelson.
The Blytheville, AR Micropolitan Statistical Area includes all of Mississippi County.
Coordinates 35°55'43.752" N -89°54'26.481" E