Cornwall County

Cornwall County may refer to:


 * Cornwall County, Province of New York, United States
 * Cornwall County, Jamaica
 * the former name of Cornwall Land District, Tasmania, Australia
 * Cornwall (Kernow), England, UK; a county, and former countdom
 * United Counties of Stormont, Dundas and Glengarry, Ontario, Canada; sometimes called "County of Cornwall"
 * Cornouaille (Kernev), Brittany, France; a former sovereign county, also spelled as "Cornwall"