Deverbal formations in Greek, e.g. "mi'razo" 'to distribute' < "'mirazma" 'distributing' are considered morphologically complex lexical items. Previous psycholinguistic studies in Greek and English already highlighted the importance of lexical category and argument structure of the base verb in the processing of deverbal pseudowords violating constraints pertaining to these properties. A similar study in Slovenian brought into light the role of aspectual properties of the base verb during deverbal word processing. The present study revisits the role of aspect in morphological processing of deverbal word formations by looking at Greek. To this end, an offline acceptability judgement task and an online lexical decision task were conducted using different types of pseudowords, violating derivational rules. Results provide evidence that aspect affects deverbal pseudoword processing in Greek. Aspectual rules have a distinct role in relation to categorial and argument structure ones for the suffix that creates formations with unambiguous, eventive readings and which has clear event implications but not for other suffixes. The current study extends the literature to include the role of this feature in the processing of deverbal formations.