ABSTRACTBackground: Alzheimer's disease (AD) is characterized by memory loss and cognitive impairment. Phonological, syntactic, semantic and discursive aspects of language may also be affected. Analysis of micro- and macrolinguistic abilities of discourse may assist in diagnosing AD. The aim of this study was to identify changes in the discourse (lexical errors and syntactic index) of AD patients.Methods: 121 elderly subjects narrated a story based on a seven-figure picture description.Results: Patients with AD presented more word-finding difficulties, revisions and repetitions, and the syntactic index was lower than controls.Conclusion: Performance in microlinguistics at the lexical and syntactic levels was lower than expected in participants with AD.