Harrison Gaston Brewer (September 21, 1855 - January 22, 1920) was an American draftsman and architect. Born in Annapolis, Maryland, Brewer moved to Washington, D.C. with his family as a child. He earned a degree in Architectural Engineering from Johns Hopkins University and worked for the Navy Department for over 30 years, most of that time spent in the Hydrographic Office as a draftsman. He married Marcie Elliot with whom he had four children, one of whom preceded him in death.