In a typically developing brain, continuing myelination of certain cortical areas and pruning of the previously established synapses represent the two most important developmental changes during the adolescence. There are several behavioral and emotional consequences of these changes. The most common projection is the turmoil of typically developing youth including the interpersonal conşicts and the task of identity formation. For some others, when the developmental trajectory shows derailment, several psychiatric clinical outcomes may emerge, necessitating professional assistance. Bipolar Disorder (BPD) and Schizophrenia share this, so called neurodevelopmental, model with a typical onset in late adolescence or early adulthood. In addition to having a similar etiological model, the two disorders may show overlapping symptom profiles especially in early onset cases. Pediatric BPD is associated with higher rates of psychosis than the adult onset form (Carlson et al. 2000). In some cases, where the psychotic features are predominant, it is difficult to differentiate the BPD and Psychotic Disorders in adolescents. It is critical, because the outcome and the psychopharmacological interventions differ in two disorders. The differentiation is based on type of the symptoms and the course of the illness. A thorough evaluation, including a detailed psychiatric history and mental status examination, is of great value. The chance of an accurate diagnosis is increased by sticking to the diagnostic criteria and by taking the characteristics of delusions and hallucinations into account. The overall course of the disorder and the patient’s level of function are, as well, the other possible indicators. The aim of this presentation is to highlight the possible indicative variables in distinguishing the pediatric BPD from Early Onset Psychotic Disorders and to review the management processes in undistinguishable cases.