Defeasible Logic Programming (DeLP) is a knowledge representation formalism that combines results from Logic Programming and Defeasible Argumentation to provide reasoning based on contradictory and potentially incomplete information. DeLP allows information representation by using weak rules and provides an argumentation inference mechanism for warranting the entailed conclusions. It is necessary to comprehend the relationships between the arguments involved in DeLP derivation to understand the reasoning process and justify the replies provided by the DeLP system. In order to reach such a degree of understanding we present DeLP Viewer, a DeLP visualization tool for representing the inference process performed by a DeLP reasoner. Albeit there are many applications designed for argumentation visualization, our proposal provides a visual representation for the underlying logic and argumentative structure behind DeLP, allowing the interactive exploration of the entire reasoning process plus the internals of the involved arguments.