The article provides the linguistic and rhetorical analysis of the mistakes made by medical students in the English abstracts. For the first time the academic abstract texts created by the native speakers of Russian are introduced into the paradigm of the academic genre study. The analysis has allowed the author to classify the students’ mistakes into groups according to their statistical value: lexico-grammatical, syntactical, stylistic and structural ones. The research findings can be used when compiling subject-oriented courses on academic English writing.