To evaluate the role of hepatobiliary (DISIDA) scan in the diagnosis of biliary obstruction, we studied the clinical characteristics of 9 cases with biliary obstructuon, whose hepatobiliary scans and ultrasonography were not concordant (normal ultrasonography and abnormal hepatobiliary scan). The results were as follows; 1) The main chief complaints (89%) were abdominal pain, especially in RUQ area. The levels of serum bilirubin were elevated in 67% of patients $(normalsim5.9mg/dl)$ and those of alkaline phosphatase were elevated in 78% of patients $(normalsim724U/L)$. 2) The final diagnoses were CBD stones (67%), tumor (22%) and 3 cases were associated with C. sinensis. 3) The major obstruction sites were in distal CBD (89%). From the above results we concluded that hepatobiliary scan is a useful diagnostic method of biliary obstruction, especially in distal CBD lesion and early stage, in spite of normal ultrasonography.