AIM: The study of the Mondor’s syndrome as a possible complication of gigantomastia. MATERIAL AND METHOD: A 49 year old woman, with gigantomastia, came to our observation for the presence of a large superficial vein of the left breast affected by thrombophlebitis, compatible with Mondor’s syndrome. RESULTS: A “Thorek” breast reduction was performed; the patient was discharged on the second postoperative day and the follow up was smooth and free from any complications. DISCUSSION: In the case we observed, gigantomastia had a clear role in the pathogenesis of the Mondor’s disease; in fact, the excessive weight of the breasts caused stretching of the mammary dorsal vein evolving in phlebitis. In literature, among the causes related to Mondor’s disease the pendulous breast is described, probably with the same dynamic we have seen in this patient, but has never reported, so obviously, the correlation between the two events. It’s considered as good practice in the pre-operative evaluation, to make differential diagnosis with any cancer, that, in a certain percentage, is associated with Mondor’s syndrome, and once established the causes of the pathology, it is imperative to eliminate them to prevent any relapses. CONCLUSION: Among the various causes recognized as predisposing to Mondor’s syndrome, there has never been described gigantomastia so far. The observation and treatment of a patient in whom the gigantomastia certainly led to the onset of Mondor’s disease, has led us to consider this as one of the possible complications of gigantomastia, providing an additional cue to the treatment of this condition even at an early stage.