In 21 patients with chronic liver disease, the ratio of liver to muscle signal intensity on T1-weighted images was negatively correlated with the progression of hepatic fibrosis defined according to findings by laparoscopy and liver biopsy, and differentiated six patients with early chronic hepatitis from eight with liver cirrhosis. On T2-weighted images, the number of low intensity nodules comparable in size to regenerating nodules surrounded by connective tissues showed a positive correlation with stage. When hepatic fibrosis with no necrosis or fat infiltration was induced in rats, T2 values were positively correlated with hepatic hydroxyproline content, though there was no such correlation for T1 values. These results suggest that MR imaging may be useful for determining the progression of hepatic fibrosis in chronic liver disease. T2 values may directly reflect hepatic fibrosis.