Paulo Santos´ constructions presents the thesis in which his history works is based on - reflex of the formations in architecture and in history - are implicit two intentions: to settle a new way to write and to teach the history of architecture in Brazil and to found a brazilian historiography of the subject, linking the teaching of architecture to his historiography project. The conductor line of the formation process of Paulo Santos as an historician of architecture was teaching at FNA/UB, because, as the cathedratic professor of Arquitetura no Brasil subject, he would consolidate the articulation between those knowledge fields, creating, that way, a singular and a brilliant trace of his professional trajetory. This work follows the time line between 1946 and 1985, according to the time production of the historic studies made by him. The subject is treated pointed to the formation as an engineer-architect and, later, as a professor in his relation with the contemporaneous; the text analyzes the structuration of the historic thought based on the dialog with brazilian historiography´s authors and establishing the his vision of architecture historician, stimulated by the interlocution with the architect Lucio Costa.