The constituent power is a concept of great importance for the political and the law theories. The merit of having been the first to conceptualize constitutional power is usually attributed to Sieyès. The present work argues that, in fact, Machiavelli had already dealt about the constitutional power in his work, although he didn’t give the phenomenon the addressed name. For so, we will demonstrate the concepts of virtù and fortune in the context of Machiavelli’s work and examine the required institutions for its conservation. Finally, the concept of constituent power will be covered, which cannot be simply trapped in the meshes of the law. Once the characteristics of the constituent power are stablished, the presence of its elements in Machiavelli will be demonstrated.