Background: renal masses are being exposed more frequently in the last decades due to advances in cross sectional imaging such as CT and MR. Accurate characterization of renal masses is essential to ensure appropriate case management, to assist in staging and prognosis and to differentiate surgical lesions from nonsurgical lesions. However, in some cases there is an overlapping between the ADC values of benign and malignant masses. Thus, the use of ADC values alone may lead to inaccurate assessment of renal masses. Aim of the Study: to assess the roles of DWI in combination with quantitative ADC measurements the differentiation between benign and malignant renal masses. Conclusion: The combination of conventional MRI and ADC value in the diagnosis of renal masses can increase the diagnostic accuracy and considered of most value in cases where IV contrast agents are contraindicating.