This study describes the relationship of irritable mood (IRR) with affective disorders in youths with attention deficit hyperactivity disorder (ADHD).Five hundred ADHD subjects were assessed with the childhood version of the Schedule for Affective Disorder & Schizophrenia. Subjects were in a genetic ADHD protocol and limited to those of Caucasian/European descent.The most prevalent concurrent diagnoses were oppositional defiant disorder (ODD) (43.6%), minor depression/dysthymic disorder (MDDD) (18.8%), and generalized anxiety (13.2%)/overanxious disorder (12.4%). IRR subjects (21.0%) compared to the non-IRR (NIRR) group had higher rates of all affective disorders (76.2% vs. 9.6%) and ODD (83.8% vs. 32.9%) but lower rates of hyperactive ADHD (1.9% vs. 8.9%). Among those without comorbidities, 98.3% were NIRR. Logistic regression found IRR mood significantly associated with major depressive disorder (odds ratio [OR]: 33.4), MDDD (OR: 11.2), ODD (OR: 11.6), and combined ADHD (OR: 1.7) but not with anxiety disorders. Among symptoms, it associated IRR mood with a pattern of dysthymic and ODD symptoms but with fewer separation anxiety symptoms. Diagnostic and symptomatic parameters were unaffected by demographic variables.Potential confounders influencing these results include patient recruitment from only one clinical service; a cohort specific sample effect because some presumed affective disorders and non-Caucasians were excluded; and the young mean age (10.2 years) limiting comorbid patterns.The prominence of an MDDD pattern suggests this IRR group is appropriate in the DSM V's proposed chronic depressive disorder, possibly with or without temper dysregulation. A new diagnosis of disruptive mood dysregulation disorder may be unwarranted.