Differentiation between benign and malignant hepatic lesions was attempted according to the shape of the lesion, internal architecture and characteristics of signal intensity on MR images. We retrospectively analyzed 20 cases of hemangiomas. 12 cases of hepatomas and 5 case of cysts which were diagnosed by clinical, radiological and surgical methods (33 patients). On T1-weighted proton weighted, and T2-weighted images, most hemangiomas (70%) and cysts (100%) had smooth margin and were round or oval in shape, while hepatocellular carcinomas had irregular (67%) or lobulated (33%) borders. Ninety percent of hemangiomas and 100% of cysts had homogeneous signal intensity, but 67% of hepatocellular carcinomas were inhomogeneous. Signal intensities of hepatocellular carcinomas were more variable. However, hemangiomas were isointense or hyperintense on proton weighted images, and markedly hyperintense on T2-weighted images. In conclusion, inhomogenous, irregular border, and variable signal intensity lesions had a high likelihood of malignancy, while homogeneous and markedly hyperintense lesions were more likely benign.