The goal of this paper is twofold. First, it aims to identify in Heidegger’s work a determination of the history of metaphysics parallel to the famous onto-theological one, and which I will label onto-agathological. Based upon a text from the course of 1935, “Einführung in die Metaphysik,” I argue that for Heidegger the history of metaphysics is not only the Aristotelian onto-theology, but is also characterized by the Platonic pre-eminence of the good over being (Republic 509c). In short, it is an onto-agathological history. Second, and as a consequence of the first point, I will flesh out the hypothesis of another history metaphysics, and emphasize its strong phenomenological content which stands in opposition to the Neo-Kantianism of Windelband and Rickert.