The aim of this paper is to examine whether and, if so, how far, the Augustinian notion of pulchrum is related to Plotinus’ concept of beauty, as it appears in Ennead I. 6. The Augustinian notion of beauty will be analyzed by focusing on the De natura boni, considering plurality and unity in Augustine’s identification of bonum with esse, both in their ontological and axiological dimensions. Topics selected for special consideration will be, first, beauty as outcome of modus, species and (...) ordo naturalis, and, secondly, corruptio as cause of deformitas. The first part of the paper will attempt to explain the Augustinian identification of esse with bonum and pulchrum.The second part will analyze Plotinus’ notion of beauty, as spelled out in Ennead I. 6, considering the Plotinian identity of to kalon and to agathon. Topics selected for analysis will be, first, the concept of form as cause of beauty, and secondly, the notion of to aischron as partial or absolute lack of form. The second part of the paper will attempt to explain Plotinus’ concept of good as yielding the nature of beauty through an analysis of Plotinus’ reflections on being and unity. The third part of this paper will consider the differences between Plotinus’ and Augustine’s identity of ugliness and non-being, as related to the notion of matter. Topics selected for analysis will be, firstly, Plotinus’ identity of matter and to aischron, and, secondly, Augustine’s concept of matter as capacitas formarum. The conclusion will prove how Plotinus’ concept of matter as coinciding with ugliness shows a wide theoretical difference between Augustine’s and Plotinus’ ontological-axiological patterns. (shrink)