Background: Non-alcoholic fatty liver disease (NAFLD) is a highly prevalent condition. Emerging evidence suggests that vitamin D may play a role in the pathogenesis of NAFLD. Aim of The Work: In this study, we tried to assess the relationship between the level of serum 25(OH) vitamin D and non alcoholic fatty liver disease (NAFLD) in various degrees of insulin-resistance and related metabolic disorders.Subjects And Methods: Patients were divided into three groups: group )A( 20 patients with (NAFLD) and diabetic, group (B) 20 patients with (NAFLD) and dyslipidemic, group (C) 20 patients with (NAFLD) but without diabetes or dyslipidemia in addition to 20 healthy age and sex matched controls. All patients enrolled in the study were subjected to full history taking, thorough examination, laboratory investigations(25(OH) vitamin D, insulin, lipid profile, blood glucose, AST, ALT). Radiological investigation was in the form of abdominal ultra sonography.Results: This study found a strong association between vitamin D defficiency and NAFLD diagnosed by ultrasound examination. This association was independent from age, sex, diabetes, insulin resistance (HOMA_IR) or liver functions. Inverse correlation between vitamin D and the lipids (LDL and TG) was evident in NAFLD diabetic group only.Concluson: In conclusion, this study found a strong association between vitamin D defficiency and NAFLD diagnosed by ultrasound examination. The contribution of vitamin D deficiency to the pathogenesis of NAFLD and the role of vitamin D supplementation for treatment or even prevention of NAFLD needs further studies