We report the case of an 80-year-old man with Frey syndrome that developed 30 years postoperatively, which is an exceptionally long period before its occurrence. Sweating and flushing occurred on only the side of his face where the surgery was performed, and he had no other causative abnormalities. Following treatment with botulinum toxin, the patient's symptoms resolved. Extremely early- and late-onset cases do not fit the conventional paradigm of this pathology. Various surgical methods to prevent this syndrome have been explored, but complete prevention has not yet been achieved. These findings suggest that the underlying pathophysiology of Frey's syndrome may be more complex than previously recognized.