This study allowed me to understand the mechanism of the United Nations, considered the largest forum for global debates, as well as the game of influence and interests within this organization. I was able to closely examine the scope of UN missions in Haiti. These peace operations are part of the international community's support to the Haitian authorities in order to contribute to the constitutional process established by the Haitian constitution of 1987. I have observed the limitations of UN missions around the world. Indeed, the mandates do not always fully correspond to the real problems of the country. This is precisely because of the strong military presence of the United Nations on the ground when Haiti is not in a context of armed conflict. The Permanent Mission of Haiti to the United Nations has a key role to play in promoting and defending the country's interests. In this regard, the State must put the economy and development at the heart of its diplomatic priorities and provide its diplomacy with the means to better exploit the vast opportunities offered by the multilateral sphere.