Two different entities by their origin, the Chadian traditional authority and the modern state administration have reciprocal obligations. Rooted in a society where it was born and which legitimated it, the former usually goes by this society to take advantage under every circumstance. The latter, product of history, considers the former as an outdated political entity. Practically, however, it can be noticed that the modern state administration often resorts to the traditional authority to get support under certain circumstances. This work, which poses the problematic of power coexistence, aims at analyzing the relationship maintained by these political entities through the regimes that have followed each other in Chad. Essentially based on written sources, this work comes up with the view that the relationships between traditional authorities and modern state administration are the relationships of domination instead of collaboration.