This article aims to evaluate the role of the patronage in the eighteenth-century France and to perceive the mechanism of political power. For these purposes, we analyze the patronage in which the Marquet participated. From this research, we find three important facts as follows : First, the affiliation to a powerful patronage was the most indispensible way to achieve the social success, to obtain the wealth and to approach the political power in the eighteenth-century France. Thanks to these patronages, the Marquet could gain lucrative offices and reach the political power. Second, the Marquet changed often their patrons. Their choices depended not on the fidelity but on the private interest and personal ambition. Therefore, the patronage hardly lasted long. Third, as against this materially based relationship, there was other type of patronage. P?ris Duverney, Marquet de Bourgade and Calonne maintained durable relations. They pursued the same financial policies, shared the same political ideal and formed a strong solidarity. The patronage based on the fidelity existed, as Roland Mousnier says, still in the eighteenth century.