Aim of this study was to compare children diagnosed with Pervasive Developmental Disorder (PDD) according to DSM-IV-TR and DSM-5 diagnostic systems. One hundred fifty children aged between 3 and 15 years diagnosed with PDD by DSM-IV-TR were included. PDD symptoms were reviewed through psychiatric assessment based on DSM-IV-TR and DSM-5 criteria. Clinical severity was determined using Childhood Autism Rating Scale (CARS) and Autism Behavior Checklist (ABC). A statistically significant decrease (19.3%) was detected in the diagnostic ratio with DSM-5. Age and symptom severity differed significantly between those who were and were not diagnosed with PDD using DSM-5. B4 criteria in DSM-5 was most common criterion. Results indicate that individuals diagnosed with PDD by DSM-IV-TR criteria may not be diagnosed using DSM-5 criteria.