Various methods to determine hepatic function have been studied, and among these, calculated maximal removal rate of ICG (ICG R-max) is more accurate and sensitive index for quantification of hepatic function. But calculation of ICG R-max is time-consuming, invasive, and expensive study, and even ICG R-max 1 day study is still complicated. So we tried to evaluated the advantage of hepatic function test using 99mTc-DISIDA plasma clearance rate. The author studied 11 cases of normal control, 4 cases of acute hepatitis, 8 cases of chronic hepatitis, and 19 cases of liver cirrhosis. The results were as follows : 1. normal control, DISIDA-K was 0.70min-1, inliver cirrhosis 0.25min-1, in acute hepatitis 0.46min-1, and in chronic hepatitis 0.14min-1. The most severe depressed DISIDA-K value was observed in liver cirrhosis. 2. Comparison of DISIDA-K value to liver function indices revealed no correlation between DISIDA-K value and serum albumin, prothrombin time, total bilirubin, SGOT, and alkaline phosphatase. 3. DISIDA-K value in liver cirrhosis with complication such as ascites, splenomegaly, esophageal varices, and hepatic coma was more decreased than without complication. With the above result, calcullation of DISIDA-K value was found easily available, accurate, and simple index for quantification of hepatic function.