This article aims to reconstruct the demographic status of Religious Orders in Asturias in the seventeenth century, an aspect unknown in the absence of population censuses that quantify the ecclesiastical population in said century. If we have censuses for the late sixteenth century, throughout the eighteenth century and the nineteenth century, the seventeenth century lacks this type of sources which would allow us to know much better the evolution of regular clergy of the region throughout the Age Modern This statement is extendable for the rest of the regions of the Crown of Castile. In sum, a first approximation will be made to the knowledge of the demographic status of this asturian social sector, through the use of different secondary sources and applying a series of basic mathematical procedures that will help fill the gap that the demographic studies of the regular clergy have in Asturias, for the Modern Age.