Mary King's Close is a historic close located under buildings on the Royal Mile, in the historic Old Town area of Edinburgh, Scotland. It took its name from one Mary King, a merchant burgess who resided on the Close in the 17th century. The close was partially demolished and buried due to the building of the Royal Exchange in the 18th century, and later closed to the public for many years. The area became shrouded in myths and urban legends; tales of hauntings and murders abounded.

The close is currently operated as a tourist attraction by Continuum Attractions.