The "rim sign" is a rim of increased hepatic activity adjacent to the gall bladder fossa and known as an useful indicator of acute cholecystitis. Also, many reports suggested that if rim sign is positive there is an increased risk for complications such as perforation and gangrene. To evaluate the usefulness of this rim sign, we reviewed 32 cases that were pathologically confirmed. The incidence of rim sign was 47% similar to other reports but with our results, the rim sign was not specific to acute cholecystitis nor indicator of increased risk for complications.