Purpose: to characterize and compare the performance of students with Attention Deficit Hyperactivity Disorder in metalinguistic skills, reading and reading comprehension in students with good academic performance. Methods: 30 participants from primary schools, of both genders, aged from 8 to 12 years and 11 months, divided into two groups: Group I consisted of 15 students diagnosed with Attention Deficit Hyperactivity Disorder and Group II composed of 15 students with good academic performance. The students were matched byage, grade level and gender. The students were submitted to Metalinguistic Skills Tests, Reading Protocol and Reading Comprehension Tests. Results: differences were found between Group I and Group II for skills regarding initial and final phonemic identification, syllable and phonemes subtraction and addition, as well as phonemic segmentation. The performance of Group I was also inferior than that of Group II, in Reading protocol and repetition of non-words. There was no statistically significant difference between the groups in reading comprehension performance. Conclusion: students with Attention Deficit Hyperactivity Disorder presented inferior performance in relation to reading protocol and in more complex metalinguistic skills, which required retention, analysis and information retrieval, when compared to the control group. In regard to reading comprehension, both groups presented lower performance, with similar results. The American Psychiatric Association 14 characterizes ADHD as a common neuropsychiatric disorder in childhood, with prevalent symptoms as inattention, hyperactivity, and impulsivity. Studies indicate that difficulties encountered in ADHD can be observed in more than one cognitive domain. The components of the executive functions most associated with possible cognitive impairments comprise planning, directed and selective attention, behavior regulation and motivation [14][15][16][17][18] , mainly caused by structural and chemical dysfunctions in the prefrontal cortex 19 . Therefore, ADHD can be understood as a disorder with heterogeneous manifestations which causes broad impairments in cognitive and interpersonal functioning, presenting behavioral changes and low school performance, as main complaints 17,18,20 . In regard to reading, studies 15,[21][22][23][24][25] indicated that students with ADHD present difficulties related to decoding, such as reading errors due to graphemephoneme mismatches, sequencing failures in reading graphemes, errors by omission and by substitution of graphemes and / or words. These difficulties are caused by attention problems and use of the working memory to manage information necessary for the phonological processing of the items, and essential for making the correct orthographic representations of the words.As for metalinguistic skills, students with ADHD present difficulties in activities which require greater attention and working memory, such as syllabic and phonemic manipulation 25. In addition, studies have shown that student...