High Quality Content by WIKIPEDIA articles! Greenup County is a county located in the U.S. state of Kentucky. It was formed in 1804. As of 2000, the population was 36,891. Its county seat is Greenup. The county is named in honor of Christopher Greenup. Greenup County is a part of the Huntington-Ashland, WV-KY-OH, Metropolitan Statistical Area (MSA). As of the 2000 census, the MSA had a population of 288,649.