This paper is aimed at comparing Pirandello’s metalinguistic reflections on the varieties of his repertoire (Italian, regional Italian, Sicilian dialect) with the use of these varieties in his autobiographic works, focusing in particular on Lettere della formazione (1891-1898), Saggi e Interventi, and his scientific essays on linguistic issues (Prosa Moderna, Per la solita questione della linugua etc.). While the relationship between Italian and dialect in Pirandello’s plays and narrative production (even his auto-translations from Italian to Sicilian and vice versa) has been largely analysed, scholars have not paid specific attention to Pirandello’s linguistic autobiography, especially to the awareness the writer displays to his linguistic choices and uses. The present study deals with this specific aspect in order to verify the relationship between the style varieties of his works and the deep perception of his multilingual repertoire together with the use of Sicilian dialect as speech code and/or expressive code.