This research starts from a brief identification of the beginning of Mexico's constitutional history, as well as the analysis of the supreme laws during the XIX and XX centuries with respect to the receiving system of international law and the hierarchy of international treaties within the legal order.Subsequently, analyzes the jurisprudential development about the validity of the constitutional block, leading to make a hard criticism regarding the implications of its restriction within a context that undoubtedly demands more than ever, respect and guarantee for human rights.