Abstract: This paper deals with the classification of archival documents of the Instituto Nacional de Infectologia Evandro Chagas, within the framework of Document Management of the Fundação Oswaldo Cruz. As an agency of the federal executive branch, Fiocruz must follow the regulations of the National Council of Archives and classify its documents according to Fiocruz´s File Documents Classification Code. It is therefore proposed to draw up a table of equivalence that lists the current classification code in the Foundation, with a functional classification plan that arrives at the documentary type, based on the functions and activities of the INI. Because they are elaborated with different methodologies - the first one is based on the subject of the documents and the second, in the functions and activities -, it is necessary to draw up the equivalence table for the functional plan to be applicable to the Institute. The methodology for the elaboration of the equivalence table is related to the comparison between the classification code by subjects and the functional classification plan. It was possible to conclude that, based on the aid of equivalence, the ideal is for each institution to elaborate its own classification plan, both of the activities-means and the end-activities, based on the functional methodology arriving at the documentary type.