Harrison is a census-designated place (CDP) in Hamilton County, Tennessee, United States. The population was 7,630 at the 2000 census. It is part of the Chattanooga, TN–GA Metropolitan Statistical Area. Harrison Bay State Park, the Hamilton County Landfill, Bear Trace Golf Course, a course designed by Jack Nicklaus, and Skull Island, a recreational area owned by TVA, are all located in Harrison.
Harrison is located at 35°7′9″N 85°8′58″W / 35.11917°N 85.14944°W / 35.11917; -85.14944 (35.119296, -85.149487).
According to the United States Census Bureau, the CDP has a total area of 9.1 square miles (23.7 km²), of which, 7.3 square miles (18.9 km²) of it is land and 1.9 square miles (4.8 km²) of it (20.33%) is water.