The Army Distinguished Service Order (Vietnamese: Lục-Quân Huân-Chương), Air Force Distinguished Service Order (Vietnamese: Không-Lực Huân-Chương), and Navy Distinguished Service Order (Vietnamese: Hải-Quân Huân-Chương) was a military decoration of South Vietnam which was awarded throughout the years of the Vietnam War.

The decoration was bestowed for meritorious or heroic deeds related to wartime operations and was awarded for both combat and non-combat service.

The first class of the order was differentiated by a blossom device centered on the medal and ribbon.

The last issuance of the Vietnam Distinguished Service Order was in 1974, before the Fall of Saigon.

The Army/Air Force/Navy Distinguished Service Order is awarded or posthumously awarded to RVN Army/Air Force/Navy Officers who meet one of the following requirements: The Army/Air Force/Navy Distinguished Service Order is also intended for Army/Air Force/Navy units and General Officers in other armed services, who have accomplished an achievement that is exceptionally important and beneficial to the Republic of Vietnam Army/Air Force/Navy.