Adena is a village in Harrison and Jefferson Counties in the U.S. state of Ohio. The population was 815 at the 2000 census.
The Jefferson County portion of Adena is part of the Weirton–Steubenville, WV-OH Metropolitan Statistical Area.
Founded in 1801 and incorporated in 1908, Adena began in a land fertile for agriculture, and in later years railroads and coal mines provided many jobs. Adena's coal mines were part of eastern Ohio's richest coal area.