Up to now, critical approach on Samuel Beckett`s plays tended to revolve around the characteristic elements of absurdity. This paper, however, attempts to show how aspects of grotesque reveal in his plays. According to John R. Clark, Samuel Beckett is doubtless the greatest purveyor of grotesque in our century. In this respects, it is required to review the conception of grotesque. According to M. M. Bakhtin, one of the essential principle of grotesque realism is degradation, that is, the lowering of all that is high, spiritual, ideal, abstract. These ideas are linked with a transfer to the material, to the sphere of earth and body in their indissoluble unity. Besides, the bodily element in the grotesque is deeply positive. It is true that Beckett`s plays have just regarded as a tragicomic absurdity, not grotesquerie. In spite of similarity between the aspects of grotesque and tragicomedy, therefore, it is worth while to distinguish the concept of tragicomedy from the grotesque. Though both manifest a dissatisfaction with rational categories, tragicomedy remains within these categories while the grotesque exposes them and simultaneously transgress them. In this light, Beckett`s plays reveal grotesquerie as well as tragicomic condition. In other words, the grotesque in the plays of Samuel Beckett plays a subversive part, which are theatrically substantiated through those grotesque image as the mound of Happy Days, the reference to Zeno`s heap of Endgame, and the image of dog related to characters in Waiting for Godot. And also in this process, the grotesque as a dramatic metaphor reveals its deterritorial function which blaze a trail to a new territory for drama through changing epistemological attitude to the world and human being.