Gallbladder (GB) cancer occurs predominately as a biliary tract malignant tumor. It generally has a very poor prognosis, and early detection is often difficult. A variety of carcinogens have been implicated as an important cause for GB cancer. Benzene is a well-known carcinogen for hematologic malignancy, and its casual relationship with GB cancer has been suggested. We report a case of two patients who had operated a laundry cleaning facility together and later simultaneously got GB cancer after prolonged benzene exposure.