<p>Cognitive disengagement syndrome (CDS) is a set of behaviors including mental confusion, excessive daydreaming, and slowed behavior and thinking that are strongly related to but distinct from attention-deficit/hyperactivity disorder (ADHD). A small body of research suggests that CDS may be associated with specific daily life executive functioning (EF) deficits in children, above and beyond ADHD symptoms. However, findings remain mixed, partially due to using smaller and ADHD-defined samples, mono-informant designs, and non-optimal measures of CDS. The current study examined multi-informant CDS and ADHD symptoms in relation to daily life EF in children (<i>N</i> = 263; ages 8–12 years; <i>M</i>±<i>SD</i>_age <i>=</i> 9.83 ± 1.42; 42.2% female). Caregivers and teachers completed measures assessing CDS, ADHD, and daily life EF. Multivariate regression analyses examined CDS and ADHD symptoms in relation to metacognitive and behavioral regulation EF domains. Across models with caregiver- and teacher-reported symptoms, ADHD-hyperactivity/impulsivity and ADHD-inattention symptoms were most consistently and strongly associated with behavioral and metacognitive EF domains, respectively. Nonetheless, even after accounting for ADHD symptoms, CDS was significantly associated with greater difficulties in metacognitive index subscales (Initiate, Working Memory, Plan/Organize, Organization of Materials, Monitor) and one behavioral regulation index subscale (Shift). This study provides evidence of the unique association between CDS and daily life EF, suggesting that CDS symptoms may be important to incorporate in models of EF. Future studies are needed to examine the interrelations of CDS and EF over time and in response to treatment.</p>