In general, comorbidity is a rule, not an exception in child psychiatry. People who meet criteria for mania almost meet criteria for at least one other disorder. ADHD, oppositional defiant disorder, conduct disorder and anxiety disorders are the most comorbidities that occur with bipolar disorders. Substance and alcohol abuse are common in adolescents who are affected. Youths with suspected diagnosis must be carefully evaluated for other associated problems specially comorbid disorders. In prepubertal children, ADHD may be found in up to 90% of cases with bipolar disorders, while only11-22% of children with ADHD also has bipolar disorder. On the other hand, differentiating ADHD from JBPD is a clinical challenge, because limited diagnostic criteria make overlapping symptoms even more difficult to interpret. But there are some tips that may be helpful like family history of bipolar disorder and symptoms which are characteristic of JBPD such as elevated mood, grandiosity and hypersexuality that are not common feature of ADHD. The appropriate management of children with ADHD and JBPD is an attainable clinical goal that should be pursued by psychiatrists. A multidisciplinary evaluation that includes a complete history, clinical interview and use of behavioral rating scales will lead to accurate diagnosis and appropriate treatment in nearly all cases.