This article focuses on an analytical approach of “security governance” in light of post-conflict situation and aims to examine a system of conflict prevention in the West African region from a viewpoint of the approach. The security governance initially developed security studies of International Relations especially for the regional governance in the field of European security. On that basis of making and developing the new perspective for the region, it currently goes to expand the subject to other regional security including Africa related to the post-conflict situation where multiple security providers are involved. In spite of needs for the further analysis, it seems that the research of security governance still deviates from the concrete study based on African cases related to the issues of reconstruction for “failed state,” due to the complexity of security governance among the public and private providers through the formal and informal interactions. In that context, after demonstrating the characteristics of security governance in post-conflict situation, this article argues distinction of security governance in Africa, especially through a practice of the security governance through “conflict prevention and early-warning system” formulated by a regional organization, the Economic Community of West African States (ECOWAS) and an organization of local civil society, the West Africa Network for Peacebuilding (WANEP), with the financial support of the United States Agency for International Development (USAID).