Merrill Anthony McPeak (born January 9, 1936) is a retired 4-star general in the United States Air Force whose final assignment before retirement was as the 14th Chief of Staff of the Air Force from 1990 to 1994.
In 1993, McPeak served as Acting Secretary of the Air Force, before Sheila E. Widnall was appointed by President Bill Clinton, and is the only Chief of Staff of the Air Force and uniformed Air Force officer on active duty to have ever served as Acting Secretary.