Arteriai fraction of total hepatic blood flow was estimated by a new method, slope method, on radionuclid angiogram using 99mTc-DISIDA and was compared with that from 99mTc-Phytate radionu clide angiogram. This study included ll of normal subjects, 37 of intermediate group with various liver diseases, and 25 patients with liver cirrhosis. We analyzed the datas with slope method from radionuclide angiograms and the results were compared with hepatic arterial fractions from uptake method, introduced by Lee et al. at 1986. The hepatic arterial fractions from radionuclide angiograms using Tc-DISIDA and 99mTc- Phytate were 0.32 +- 0.09 and 0.31 +- O.11 respectively in normal subjects, and 0.75+0.18 and 0.77+0.21 respectively in patients with liver cirrhosis. The hepatic arterial fractions by the slope method was well correlated with those of the uptake method on 99mTc-DISIDA scan. There was high correlation between the hepatic arterial fractions from 99mTc-DISIDA and 99mTc-Phytate scans. Hepatic arterial fraction estimated by the slope method is a useful index for the diagnosis of liver cirrhosis and the evaiuation of status of portal hypertension.