Blennerhassett is a census-designated place (CDP) in Wood County, West Virginia, United States.

It is part of the Parkersburg-Marietta-Vienna, WV-OH Metropolitan Statistical Area.

[citation needed] According to the United States Census Bureau, the CDP has a total area of 5.0 square miles (13.0 km2), all land.

At the 2000 census,[2] there were 3,225 people, 1,227 households and 996 families living in the CDP.

16.9% of all households were made up of individuals, and 5.8% had someone living alone who was 65 years of age or older.