It is well established that ultrasonography and hepatobiliary scintigraphy are sensitive in the detection of gallstones and acute cholecystitis respectively. Both, however, seem to have shortcomings in that the sensitivity of the former in the diagnosis of acalculous cholecystitis is not sufficiently high and the latter cannot reveal gallstones. We have examined 44 patients with suspected cholecystitis by these two diagnostic modalities. Their overall correlation was 86.3%. Ultrasonography, which should be the first examination of the gallbladder, was usefully supplemented by the scintigraphy.