This study focuses on the protection of terrorism suspects under International Humanitarian Law. This study makes Guantanamo Bay in Cuba a case study. The central themes of this study is the question on whether Guantanamo bay detainees are entitled for prisoners of war status or and also this study deals with the legal position for detainees suspected of terrorism acts during peacetime. These are main issues the field study has attempted to address. The study has revealed that every component of the ‘war on terrorism'', every situation in which persons held in Guantánamo were involved and every individual detained there has to be qualified separately. Many persons held in Guantánamo are not at all covered by international humanitarian law (IHL). Others benefit from the fundamental guarantees of International Humanitarian Law of non-international armed conflicts, which do not offer a legal basis for their detention an issue dealt with by domestic law. The study has also shown that those persons who were arrested in Afghanistan are protected by International Humanitarian Law of international armed conflicts..