Clemson is a city in Pickens and Anderson counties in the U.S. state of South Carolina. Clemson is adjacent to Clemson University, and is id…Clemson is a city in Pickens and Anderson counties in the U.S. state of South Carolina. Clemson is adjacent to Clemson University, and is identified with it; in 2015, the Princeton Review cited the town of Clemson as ranking #1 in the United States for "town-and-gown" relations with its resident university. The population of the city was 17,681 at the 2020 census.