A 77-year-old female with a chief complaint of epigastralgia was diagnosed with torsion of the gallbladder by abdominal CT prior to surgery and successfully treated by an emergency operation. Only 16 cases of gallbladder torsion including the present case have been diagnosed prior to surgery in Japan. Almost all of them were diagnosed with abdominal ultrasonography. With the growing use of CT in the evaluation of abdominal pain, preoperative diagnosis of the condition may be expedited. CT shows characteristic findings of torsion of the gallbladder such as 1) pronounded swelling of the gallbladder and circumscribed thickening of the gallbladder wall, 2) displacement of the gallbladder, and 3) volvulated gallbladder neck. We found CT to be useful for preoperative diagnosis of patients with abdominal pain.