Background: According to the high prevalence of non-alcoholic fatty liver and high rates of ultrasonography candidates for diagnosis of this disease, the aim of this study was to determine the agreement between ultrasound and computed tomography (CT) scan in diagnosis of non-alcoholic fatty liver.Methods: In a cross-sectional study conducted in 2018 at Ali ibn Abitaleb hospital in Rafsanjan, Iran, 100 patients with abdominal CT scan who were suspected to metabolic syndrome were enrolled. All patients underwent CT scan and liver ultrasonography. The degree of agreement between ultrasound and CT scan was investigated in diagnosis of fatty liver.Findings: Fatty liver was diagnosed in 68 patients (68%) in ultrasound and CT scan diagnostic methods; and was not diagnosed in 18 patients (18%) by both diagnostic methods. In contrast, although in 8 patients (8%) fatty liver was found in ultrasonography, they were normal in the CT scan. Six patients (6%) also showed fatty liver in CT scan, while fatty liver was not diagnosed in ultrasound assessment. Overall, the agreement between CT scan and ultrasound findings was 0.63 (P < 0.001).Conclusion: The results of the present study showed that there was a good agreement between ultrasonography and CT scan findings in determining non-alcoholic fatty liver. It seems that ultrasonography is a good diagnostic method for the evaluation of patients with suspected liver transfusion.