Arriving off South Vietnam in April 1966 the destroyer shelled Vietcong supply points and encampments for the next 4 months. After a short break, "Morton" began Sea Dragon operations off North Vietnam in May 1967. During these raids, she targeted enemy coast defense sites and radar installations and interdicted barge traffic along the coast. "Morton" also provided gunfire support for the 12th Marine Regiment near the DMZ before returning to San Diego 3 November.