This dissertation deals primarily with migrant children and the determination that they are persons under 18 years of age, third-country nationals or stateless persons, and are outside their countries of origin in the territory of another state without legal conditions for departure and stay, with or without a legal guardian and with or without proper care. The phenomenon of migrant children is widely recognized as a major international problem that has become more pronounced in Europe in the last ten years. The number of migrant children trying to enter Europe and especially the territory of the European Union is increasing dramatically. In doing so, children are exposed to serious dangers and violations of basic human rights. Due to the difference in approach to this problem in the EU country, there are growing efforts for EU member states to adopt a unified policy and appropriate measures. We are witnessing a time when they are on the borders between the countries that are members of the European Union and those that are not undergoing increasingly strict controls, especially because of the threat of terrorism. There are a number of reasons why children migrate. Among them are the search for a better life, escape from poverty, political conflicts, wars and persecutions, loss of family security or natural disasters and many children carry with them memories of the horrors they experienced in their homeland or later on the path to desired security. Like their other children, unaccompanied children should have access to rights and be protected in accordance with the provisions of the Convention on the Rights of the Child, regardless of their immigrant status. Precisely because of this, this paper attempts to answer the question of whether child protection legislation can migrate adequately to address this problem in Europe and the world.