IV Corps tactical zone

During the Vietnam War, the IV Corps tactical zone (IV CTZ) was an Army of the Republic of Viet Nam organization with geographic responsibility for the Mekong Delta provinces, including much of the classic area of Cochin China less the Saigon area.

III CTZ headquarters was at Can Tho, a suburb northeast of Saigon. There was no regular U.S. tactical counterpart organization, although there was a senior advisor at Can Tho.