In new just war theory Post-war accountability is one of the most important section of jus post bellum.The establishment and implementation of Post-conflict accountability mechanism should follow the essential requirement of laws of post-conflict phase which aims to achieve durable peace.There are various types of accountability mechanisms including judicial and non-judicial measures to choose when a country or international community is thinking them over thougth a national or international manner.Attention should be paied in this phase including the special status of post-conflict phase，the impact of local Legal tradition，the legal environment of international community and so on.The central task to establish post-conflict accountability mechanism at present is to withdraw adverse effects of realpolitik and to develop principles and norms of jus post bellum to clarify post-conflict accountabilities.