Five ships of the United States Navy have been named USS Essex, after Essex County, Massachusetts.

USS Essex (CV-9) (also CVA-9 and CVS-9) was a United States Navy aircraft carrier, the lead ship of her class.

USS Essex was an ironclad river gunboat of the United States Army and later United States Navy during the American Civil War. It was named for Essex County, Massachusetts.

The first USS Essex of the United States Navy was a sailing frigate that participated in the Quasi-War with France, the Barbary Wars, and in the War of 1812, during which she was captured by the British (1814).