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

[5] It is included in the Morgantown, West Virginia Metropolitan Statistical Area.

[1] According to the United States Census Bureau, the Cassville CDP has a total area of 9.2 km2 (3.6 sq mi), all land.

As of the census[4] of 2000, there were 1,586 people, 644 households, and 446 families residing in the CDP.

25.5% of all households were made up of individuals, and 12.0% had someone living alone who was 65 years of age or older.