Introduction: Specific learning disorders (SLD) is reported in 8 to 10% of the general population. This condition is often associated with ADHD (33 to 70%). These neurodevelopmental disorders are commonly associated with various comorbidities such as anxiety-depressive disorders. Previous studies, based on questionnaires, exhibited more sleep troubles in comparison to control children, especially in children with SLD and ADHD. The aim of this study was to evaluate sleep characteristics in children with SLD with or without ADHD addressed in Sleep clinics for Sleep complaints. Method: One hundred and eight children (46 girls) with SLD, median age 11.9 (range 5.2 to 18.2 years) were included in this retrospective study. The patients were divided into 4 age-balanced groups: SLD only (n = 39), Multi -SLD (n = 24), SLD-ADHD (n = 16), and Multi-SLD-ADHD (n = 29). For each patient, the medical history, sleep complaints, the somnolence score (Epworth sleepiness scale), the results of the polysomnography were collected from medical charts. Statistical analyses were done to compare the different groups with non-parametric tests (Kruskal Wallis and Khi²). Results: Dyslexia was the most prevalent SLD (65.1% without ADHD, and 73.3% with ADHD). Multi-SLD had a higher frequency of ADHD (64.4% versus 38.1% without ADHD). Children with SLD had elevated frequency of allergies and asthma. The main sleep disorders found were respiratory issues, usually mild OSA and UARS (80%), PLM (30%) and sleep fragmentation (55%). Comparisons revealed differences based on psychostimulant treatment, with lower levels of drowsiness and increased insomnia associated with such treatment. Conclusion: This study highlights a significant proportion of comorbidity in SLD with possible impact on sleep. Frequent complaints of drowsiness and insomnia are present, with a difference in the type of complaint depending on whether taking a stimulating treatment. These results underline the importance of taking into account the associated comorbidities in SLD children with or without ADHD.