The thesis focuses on the Vietnamese side of the Vietnam War. Though this war is one of the wars best documented, literature about the Vietnamese side is much less in comparison with that about the American side. In the war, inherited from the long history of national defence and influenced by Marxism-Leninism on war and army, North Vietnam applied the Vietnamese strategy of people's war.calling all Vietnamese people to participate in national effort to fight against American aggression. The North Vietnam's military strategy was not consistent with the basic principles of the laws of war as it did not distinguish combatants from non-combatants. This strategy put civilian population at risk. However, the thesis demonstrates through original archive and interview based research how the People's Army of Vietnam (PA VN) was not unrestrained. It had its own rules of engagement in fighting as well as in everyday contact with civilian, in order to minimize civilian casualties and protect civilian lives and assets. Also, PAVN paid great attention to winning and maintaining support of civilian as this support was crucial for its own existence as well as its war fighting capability. One implication of studying the North Vietnam's way of war is that North Vietnam's war against America was not immoral. It also has implications on the debate about the morality of American war in Vietnam and reflection to the American's current counterinsurgency doctrine - the Petraeus Doctrine.