http://en.wikipedia.org/wiki/Vietnam_warCasualties
Main article: Vietnam War casualties
Estimating the number killed in the conflict is extremely difficult. Official records from North Vietnam are hard to find or nonexistent and many of those killed were literally obliterated by bombing. For many years the North Vietnamese suppressed the true number of their casualties for propaganda purposes. It is also difficult to say exactly what counts as a "Vietnam war casualty"; people are still being killed today by unexploded ordnance, particularly cluster bomblets. More than 40,000 Vietnamese have been killed so far by landmines and unexploded ordnance.
Environmental effects from chemical agents and the colossal social problems caused by a devastated country with so many dead surely caused many more lives to be shortened.
The lowest casualty estimates, based on North Vietnamese statements which are now discounted by Vietnam, are around 1.5 million Vietnamese killed. Vietnam's Ministry of Labor, War Invalids and Social Affairs released figures on April 3, 1995, reporting that 1.1 million fighters—Viet Cong guerrillas and North Vietnamese soldiers—and nearly 2 million civilians in the north and the south were killed between 1954 and 1975. Other figures run as high as 4 million civilian casualties with 1 million casualties being NVA or VC fighters. Robert McNamara, in his regretful memoir of the war, references a figure of 3.2 million. The number of wounded fighters was put at 600,000. It remains even more unclear how many Vietnamese civilians were wounded.
Of the U.S. military, 58,226 were killed in action or classified as missing in action. A further 153,303 US military personnel were wounded to give total casualties of 211,529. The United States Army took the majority of the casualties with 38,179 killed and 96,802 wounded; the Marine Corps lost 14,836 killed and 51,392 wounded; the Navy 2,556 and 4,178; the Air Force lost 2,580 and 931; with the lowest deaths in terms of numbers and percentages among the branches being the Coast Guard, with seven dead and 60 wounded.
U.S. allies took casualties as well. South Korea provided the largest outside force and suffered between 4,400 and 5,000 killed full details including WIA and MIA appear difficult to find. Australia lost 501 dead and 3,131 wounded out of the 47,000 troops they had deployed to Vietnam. New Zealand had 38 dead and 187 wounded. Thailand had 351 casualties. It is difficult to locate accurate figures for the losses of the Philippines. Although Canada was not involved in the war, thousands of Canadians joined the U.S. armed forces and served in Vietnam. The US fatal casualties include at least 56 Canadian citizens. It is difficult to estimate the exact number because some Canadians crossed the border to volunteer for service under false pretenses whereas others were permanent residents living in the United States who either volunteered or were drafted. See also Canada and the Vietnam War.
In the aftermath of the war many U.S. citizens came to believe that some of the 2,300 US soldiers listed as Missing in Action had in fact been taken prisoner by the DRV and held indefinitely. The Vietnamese list over 200,000 of their own soldiers missing in action.