Objective To analyze the correlation between serum 25- hydroxyvitamin D level and nonalcoholic fatty liver disease( NAFLD),and to provide a clinical basis for the prevention and treatment of NAFLD. Methods From March to October,2014,200 Uyghur patients and 200 Han patients with NAFLD in our hospital were enrolled into NAFLD group,while an equal number of healthy Uyghurs and Hans were used as controls. For all subjects,questionnaire survey,physical examination,abdominal ultrasound examination,and blood biochemical examination were performed,and serum 25- hydroxyvitamin D level was determined using enzyme- linked immunosorbent assay. The relationship between 25- hydroxyvitamin D and NAFLD was analyzed by Spearman correlation analysis and multivariate logistic regression analysis. Results Serum 25- hydroxyvitamin D levels in the NAFLD group were significantly lower than those in the control group for both Uyghurs and Hans( P < 0. 05),and serum 25- hydroxyvitamin D level was negatively correlated with NAFLD( rHan=- 0. 212,rUyghur=- 0. 220,P < 0. 01). The results of multivariate logistic regression analysis showed that the rising serum 25- hydroxyvitamin D level was a protective factor for NAFLD( ORHan= 0. 894,PHan= 0. 015; ORUyghur= 0. 897,PUyghur= 0. 025). Conclusion Serum 25- hydroxyvitamin D level is closely associated with NAFLD in Uyghurs and Hans.