Thirty tumors in 25 patients with hepatocellular carcinoma were examined by magnetic resonance imaging (MRI)with 2.0 Tesla superconductive magnet to evaluate the morphologic characteristics and signal intensity of thetumor, Identical multislice/multiecho spin-echo techniques were used in all patients. T1-and T2-weighted imageswere obtained with TRs 500, 1500 and 2000 msec and TEs 30, 60, 90, 120, 150 and 180 msec. MRI could detect tumorsin all patients. Morphologic characteristics of hepatocellular carcinomas were capsule with low-signal intensityon T1-and T2-weighted images (43%), irregular, ill-defined margin (43%), and heterogeneous internal architecture(73%). Signal intensity of the tumor was iso- or high on T1-weighted imges, and high signal intensity onT2-weighted images in all cases. Signal intensity ratio between the tumor and surrounding liver parenchymaincreased with prolongation of TR and TE up to TR 2000 and Te 120msec, and decreased with TR 2000 and Te 180 msec.Regenerating nodule with low-signal intensity on T1- and T2-weighted images were identified in 19 cases (83%) of23 patients with liver cirrhosis. Tumoral invasion of portal vein was seen in six patients. Signal intensity ofthrombus in portal vein was same as that of primary heaptic tumor. In two cases of recurrent hepatocellularcarcinomas after surgery, artifact from metallic clip was minimal as compared with that on CT scans. On the basisof our results, we believe that MRI is useful in the evaluation of hepatocellular carcinomas. Advantages of MRI inthe evaluation of heaptocellular carcinomas are differetiation of hepatoma from hemangioma and regeneratingnodules of liver cirrhosis, identificationof angioinvasion of the tumor, and postoperative follow-up in case ofsurgery with metallic clip.