The article deals with one of the issues that are shaping the internal relations between the human tissues of the state, namely the issue of ethnic diversity and multilingualism in one country. The Belgian model in the European continent is one of these models, where a group of different ethnicities coexists in the heart of this country (German, French and Dutch), in addition to the richness of the State from the linguistic side, so that the Constitution legally adopts a set of official languages ​​(German, French and Dutch). The distinction in the Belgian model is the ability of the state to adapt its political form, This ethnic diversity contain the linguistic diversity, and the adoption of legal and constitutional mechanisms to manage