BACKGROUND: Misophonia is a condition characterized by a reduced tolerance to certain sounds and strong emotional, physiological, and behavioral responses. Existing research on the relationship between misophonia and psychopathologies in children remains limited. To our knowledge, the relationship between Cognitive Disengagement Syndrome (CDS), formerly known as sluggish cognitive tempo, and attention deficit hyperactivity disorder (ADHD) and misophonia has not been investigated to date. In this study, we examined the relationship between misophonia and ADHD and CDS symptoms and possible mediating factors. METHOD: The study included 53 adolescents diagnosed with ADHD and a control group of 50 adolescents without ADHD. All participants underwent a semi-structured clinical interview using the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version, Turkish version (K-SADS-PL). Misophonia symptoms were assessed with the Amsterdam Misophonia Scale-Revised (AMISOS-R). In contrast, CDS symptoms were measured using the Sluggish Cognitive Tempo Self-Report Scale (SCT-SR). ADHD symptom severity was evaluated using the Turgay DSM-IV-Based Disruptive Behavioral Disorders Screening and Rating Scale (T-DSM-IV-S), which the participants' parents completed. RESULTS: AMISOS-R scores were higher in adolescents with ADHD compared to the control group. The AMISOS-R revealed significant correlations with ADHD-hyperactivity/impulsivity (r = 0.291), ADHD-inattention (r = 0.513), and SCT-SR (r = 0.661) symptoms. As a result of regression analysis, ADHD-inattention severity (β = 0.745, p < 0.001) emerged as the variable that was significant with adolescent misophonia severity, independently of other variables.The mediation test using the bootstrap method showed that the indirect coefficient for SCT-SR in the relationship between T-DSM-IV-S Inattention and AMISOS-R was significant, and consistent with partial mediation. CONCLUSION: Our findings indicate that symptoms of misophonia are significantly associated with ADHD and CDS symptoms, and the importance of recognizing the comorbidity of misophonia in ADHD patients. Notably, although ADHD-inattention was associated considerably with misophonia, this association was mediated by CDS severity. Therefore, when assessing individuals with symptoms of misophonia, it is important to screen specifically for ADHD-inattention and CDS symptoms as well. Further research is needed to explore these relationships in more detail and to expand our knowledge of the underlying mechanisms.