The restoration of modern architecture presents a great challenge today, since modernism breaks relations with the traditional past and creates a new architectural language. The Cathedral of Brasilia, with characteristics such as new materials, new technologies, new infrastructure systems, poses challenges to contemporary thinking, particularly on how to evaluate and intervene in this architecture, when there are not well-defined criteria to guide these activities. This paper aims to make a critical analysis of the work done in the Cathedral of Brasilia, as well as to report the intervention criteria that have been and should be applied in both theory and practice.