Marvin Kirkland "Kirk" Cox (born August 17, 1957) is an American politician and former educator.
A Republican, he has served in the Virginia House of Delegates since 1990, representing the 66th District, made up of the southern Richmond suburb of Colonial Heights and nearby parts of Chesterfield County.
He also serves as the 55th Speaker of the House of Delegates.
Prior to that, he had served as House Majority Leader since December 2010, and before that House Majority Whip from 2004 to 2010.