Background: Juvenile Idiopathic Arthritis (JIA) is a chronic rheumatic disorder commonly affecting children younger than ۱۶. The incidence and prevalence of JIA can vary greatly depending on ethnicity, genetic background, and socioeconomic status within different populations. Epidemiological studies play an essential role in planning successful treatment for chronic diseases like JIA and providing appropriate care measures in specific geographic regions.Methods: In this cross-sectional study, ۱۴۹ children were referred to the pediatric rheumatology department of Akbar Hospital in Mashhad from ۲۰۱۶ to ۲۰۱۹. Data was collected from all children within the first six months of disease onset, including the number of affected joints, demographic characteristics, systemic symptoms, extra-articular manifestations, and medication regimens.Results: The most prevalent subtype of JIA is Oligoarticular, followed by Systemic JIA at ۲۵.۵%. Among children with enthesitis-related arthritis, more girls than boys were affected. Additionally, the most frequently affected joints in children were those of the lower limb. ۵.۴% of the total, had involvement of lumbosacral and sacroiliac joints. Serositis was observed in ۲% of the patients. Uveitis was detected in ۴ out of ۱۵۴ patients (۲.۶%); ۳ of these cases were chronic anterior uveitis, while one was acute anterior uveitis. ۳ children (۲%) were reported to have Macrophage Activation Syndrome (MAS).Conclusion: Diagnosing juvenile idiopathic arthritis and other rheumatic diseases in children can often be delayed due to physicians’ lacking adequate clinical knowledge. To properly manage this chronic childhood illness, it is crucial to identify its symptoms and clinical course. This study represents the most comprehensive research conducted on children with JIA in the Northeast of Iran.