Chautauqua County is located in wetsern New York. Chautauqua County has a total area of approximately 1500 square miles of which 71% is land and 29% water.As of the census of 2000, there were 139,750 people, 54,515 households, and 35,979 families residing in Chautauqua County, New York. It is the nineteenth most populous county in New York state. Chautauqua County is the western most county in New York, with Lake Erie on its northern border. Its name is a contraction of a Seneca Indian word meaning "where the fish was taken out."