We examined patients with suspected acute or intermittent biliary obstruction using hepatobiliary scintigraphy, ultrasonography and contrast cholangiography. Of 16 patients with confirmed common bile duct obstruction, sonography and scintigraphy disagreed in 8(50%). Scintigraphy revealed partial or complete common bile duct obstruction in 13 patients (81.3%) and 6 of them had no evidence of dilated biliary trees. It is concluded that disagreement between sonography and scintigraphy is not rare in patients with acute or intermittent biliary obstruction and hepatobiliary scintigraphy is useful in diagnosing obstruction prior to ductal dilatation.