Background: The clinical importance of NAFLD and the limitations of liver biopsy have increased the need for accurate and noninvasive imaging methods to evaluate NAFLD. Acoustic radiation force impulse (ARFI) imaging is a new and promising ultrasound-based diagnostic technique that, evaluating the wave propagation speed, allows the assessment of the tissue stiffness. Aim of study: Assess the reliability of acoustic radiation force impulse (ARFI) for diagnosis of liver fibrosis in patients with non-alcoholic fatty liver disease (NAFLD) compared with NAFLD-fibrosis score and FIB-4 Index. Methods: This study was conducted on 100 patients diagnosed with NAFLD and 30 healthy subjects referred from Damanhour Medical National Institute outpatient clinics, from June 2018 to December 2018. Results: The degree of agreement between ARFI and FIB-4 index is 80%. The ROC curve for the performance of ARFI in prediction of F3 or more (taking FIB-4 as a gold standard) shows sensitivity of 100% and specificity of 79.5%. It also showed that the degree of agreement between ARFI and NAFLD fibrosis score is 87.1%. The ROC curve for the performance of ARFI in prediction of F3 or more (taking NAFLD Fibrosis Score as a gold standard) shows sensitivity of 71.4% and specificity of 83.3%.  Conclusion: The degree of agreement between ARFI on one hand and FIB-4 score and NAFLD fibrosis score on the other hand is acceptably high and is statistically significant.