Statement of Problem: Congenital missing tooth is the condition of having genetically one or more missing teeth which cannot be observed clinically or in radiographic images. This is one of the most prevalent anomalies in dental development that occurs either individually or as symptoms of a syndrome. Moreover, for permanent teeth, it is common with a reported prevalence of between 1.6-9.6%.Purpose: The aim of this study was to assess the prevalence rate and the pattern of congenital missing teeth in adolescents referring to Mashhad School of Dentistry.Materials and Method: In this cross-sectional study, a total of 600 panoram-ic radiographs related to the subjects aged 9-14 years (351 girls and 249 boys) were analyzed. The data were recorded in the related forms, and then analyzed using Chi-square and Exact tests.Results: Among 600 panoramic radiographs, 94 teeth were found to be missi-ng. The most and the least frequent missing teeth were the mandibular second premolars and the maxillary central incisors (observed in only 1 subject), respectively. The most commonly absent teeth were the mandibular second premolars, the maxillary lateral incisors, the mandibular central incisors, and the maxillary second premolars in order of the frequency.Conclusion: This study revealed that the frequency of missing tooth in girls is higher than that in boys. Thus, due to the girls' more aesthetic sensibility and also intricate treatment of such anomaly, accurate and frequent examination of adolescents’ particularly girls’ teeth for on-time diagnosis is crucial.