Kevin P. Byrnes (born 12 March 1950) is a retired United States Army general who was officially relieved of command in August 2005 after 36 years of military service for disobeying a lawful order from Army Chief of Staff Peter Schoomaker.

Byrnes' other key assignments include: Commanding General, 1st Cavalry Division, Fort Hood, Texas; while deployed in that capacity, he simultaneously served as the Commanding General of the Multinational Division (North) in Tuzla, Bosnia, from October 1998 to August 1999; Director, Force Programs, Office of the Deputy Chief of Staff for Operations and Plans, Washington, D.C.; Assistant Division Commander (Maneuver), 1st Cavalry Division; Commanding General, Joint Task Force Six, Fort Bliss, Texas; Commander, 1st Cavalry Division Artillery, and later Chief of Staff, 1st Cavalry Division; Director of Political and Economic Studies and Director of the Strategic Outreach Initiative for the United States Army War College, Carlisle Barracks, Pennsylvania; Commander, 4th Battalion, 3rd Field Artillery Regiment in 2nd Armored Division (Forward) in Germany; and Commander, Battery C, 1st Battalion, 39th Field Artillery, Fort Bragg, North Carolina.

Byrnes was relieved of command in August 2005 following revelations that he had engaged in an extramarital relationship with a married female civilian.

[4] An investigation into the alleged misconduct by the Department of Defense Inspector General had concluded that Byrnes, who was separated from his wife, had conducted an adulterous affair with a married women for approximately a year and a half; continued the affair after being ordered by Army Chief of Staff, Peter Shoomaker, to cease contact with the woman; had repeatedly used government funded hotel rooms for adulterous trysts; and had violated U.S. Army financial management regulations by using his personal credit card rather than a government travel card to pay for expenses arising from official government travel.

He also has a daughter and two sons from a previous marriage: Patrick, an architect and Joseph, an Army officer.