Few cases of volvulus of an appendiceal mucocele have been reported. The mechanism of torsion seems to be similar to that suggested for ovarian or appendegeal torsion, where a solid organ or mass fixed onto a narrow stalk is a precondition. We report the case of a young woman who presented with signs and symptoms of acute appendicitis. Computed tomography showed a cystic mass of fluid consistency in the right lower quadrant. An emergency laparoscopy revealed a 720 degrees torsion of a gangrenous mucocele around the proximal part of the appendix. We performed a laparoscopic appendectomy and she recovered uneventfully. The presentation of volvulus of an appendiceal mucocele can mimic other common conditions. Prompt surgical intervention is essential to prevent gangrene and perforation. The combination of a cystic, right lower quadrant mass, and clinical findings suggestive of acute appendicitis should alert the clinician to include volvulus of an appendiceal mucocele in the differential diagnosis.