Mercer County

Mercer County is the name of several counties in the United States, the most populous being Mercer County, New Jersey.

Other U.S. counties named Mercer include:
 * Mercer County, Illinois
 * Mercer County, Kentucky
 * Mercer County, Missouri
 * Mercer County, North Dakota
 * Mercer County, Ohio
 * Mercer County, Pennsylvania
 * Mercer County, Virginia, has existed twice; the two counties continue in existence with the same name in Kentucky and West Virginia
 * Mercer County, West Virginia