An increased awareness of IgG4-related diseases has led to an escalation in the number of sites known to be involved by this fibroinflammatory disease. We report three cases of IgG4-related cholecystitis which were thought to represent biliary malignancies both clinically and radiographically. All three cases underwent surgery tailored towards presumed malignant neoplasms. Only following pathologic examination was the true nature of the disease identified. Recognition of the clinical, radiographic, and pathologic presentation of IgG4-related cholecystitis is essential for the consideration of this disease process prior to surgical management for suspected gallbladder malignancies. However, the pre-operative diagnosis remains challenging and extensive surgical intervention is often necessary given the distressing presentation of IgG4-related cholecystitis.