Nine surgically proven congenital absence of gallbladder (CAGB) cases were reviewed. All of them had one or more kinds of biliary symptom. Tests such as abdominal ultrasonography, intravenous or oral cholecystography and even endoscopic retrograde cholangiography not only failed to predict CAGB but misleadingly indicated other similar conditions. Only the abdominal computed tomography (CT), performed on one patient, enabled the accurate diagnosis of CAGB. All the patients underwent abdominal exploration, and CAGB was confirmed by the meticulous dissection of the entire extrahepatic biliary tree and the operative cholangiography. Five patients had concomitant biliary pathologies responsible for their symptoms, but four patients had isolated CAGB. CAGB is a rarely encountered condition for a clinician, but extensive diagnostic work-ups including abdominal CT should be performed in all situations where CAGB is suspected. Thus unnecessary exploration can be avoided in the isolated CAGB case.