The reflection upon the construction of knowledge in epidemiology is increasing. To what extent this theoretical interest refers to a broader preocupation with the humanization of science? Or is it restricted to the search of legitimation of authority and scientific competence, according to the dominating rationality? This work analyses the development of epidemiology, its institutiona-lization as scientific discipline and the method's hegemonic conception built within this process. It also analyses the introduction of the Popperian thought, who was a critic in the internai debate of the american epidemiology. Finally, it refers to methodological alternatives mentioned by some authors in face or questions and impasses identified in the development of the discipline.