Abstract Background: Vitamin D has diverse immunomodulatory, anti-inflammatory, antioxidant, and anti-fibrotic actions, that have warranted its consideration as acritical pathogenic factor in the occurrence and severity ofdiverse immune-mediated diseases, including autoimmunehepatitis. Aim of Study: Primary aim: To assess serum levels of 25(OH)D in children and adolescents with AIH, Secondary aim: To evaluate the association between serum 25(OH)D levels and clinical, histological, biochemical features of AIH, Tertiary aim: To evaluate the association between serum 25(OH)D levels and response to immunosuppressive therapy. Patients and Methods: This controlled cross sectional study was performed on a total of 30 children and adolescences diagnosed with autoimmune hepatitis following-up in Pediatric Hepatology Clinic, Faculty of Medicine, Ain Shams University. They were 13 males and 17 females, their age ranged from 5-17 years old and 15 age and sex matched children as control group starting from October 2021 till July 2022. Results: This study study results revealed that there were no statistically significant differences between vitamin D level and sex, treatment, symptoms (right hypochondrial pain and abdominal enlargement), other autoimmune diseases of thyroid and DM and interface hepatitis. Conclusion: As evident from the current study, severe vitamin D deficiency occurs in patients with AIH. Interface hepatitis was found in 93.3%, bridging fibrosis in 86.7% and lymphocytic infiltration in 80% in case group of autoimmune hepatitis. Abdominal enlargement is the most common symptom in liver disease (46.7%) followed by right hypochondrial pain (26.7%).