L’articolo affronta le annotazioni depositate da Vittorio Alfieri nei margini e nelle carte di guardia di libri legati a questioni linguistiche. Si propone un percorso cronologico, dalle annotazioni dei primi anni della “conversione” alfieriana alla letteratura, fino alle postille della maturità. Particolare attenzione è rivolta alle annotazioni del periodo 1778-1779, in cui Alfieri condusse studi intensivi della lingua italiana. Quattro tipi di annotazione sono descritti: postille lessicali, razionalizzazione di grammatiche e testi teorici, osservazioni grammaticali e postille «petulanti». Alfieri continuò a studiare l’italiano lungo tutto l’arco della sua vita: ma il modo in cui annotava i testi di lingua è cambiato nel tempo parallelamente al raggiungimento della piena competenza linguistica. Alfieri and "language books"The paper focuses on annotations jotted down by Vittorio Alfieri in the margins and endpapers of books related to language issues. A chronological path is sketched, from annotations dating from the first years of Alfieri’s « conversion » to literature, to annotations dating from is maturity. Special attention is paid to annotations dating from 1778-1779, where Alfieri carried on intensive studies of Italian language. Four type of annotation are described: lexical annotations; rationalisation of grammars and theorical texts; grammatical observations and ‘petulant’ annotations. Alfieri kept studying Italian language throughout his life: but the way he annotated books concerning language issues gradually changed over the time, as he achieved language proficiency., The paper focuses on annotations jotted down by Vittorio Alfieri in the margins and endpapers of books related to language issues. A chronological path is sketched, from annotations dating from the first years of Alfieri’s « conversion » to literature, to annotations dating from is maturity. Special attention is paid to annotations dating from 1778-1779, where Alfieri carried on intensive studies of Italian language. Four type of annotation are described: lexical annotations; rationalisation of grammars and theorical texts; grammatical observations and ‘petulant’ annotations. Alfieri kept studying Italian language throughout his life: but the way he annotated books concerning language issues gradually changed over the time, as he achieved language proficiency.