The development of a phenomenological ontology was a possibility inserted in the Husserlian philosophical project. In which sense, however, the spirit of the maxim of "the return to the same things" was used as an inspiration to the return to the question of the Being? In which extent the ontological elaborations that have incorporated the title of phenomenological remained faithful to the general spirit and to the formal guidelines of Husserl's thought? In an attempt to answer these questions, this brief study aims at examining the special position of Heidegger in face of the problem of the articulation between the ontology ant the phenomenology. Our preference is dictated by the originality itself of the utilization of the phenomenology by author of Being and Time. The examination of the sense that phenomenology assumes as ontology of the comprehension, whose instrument is the hermeneutic of the factual existence of the man, requires a previous outlining of Heidegger's philosophical fundamental project.34285101