Ectopic mammary gland tissue in the vulva is an exceptionally rare disease. We present a case of a 62-year-old woman with a left vulvar mass of 30 years duration that progressively increased in size. The patient reported having pressure and discomfort, especially during movement. Surgical excision was performed, and a histopathological examination revealed a well-differentiated ectopic breast. We also review other cases of vulvar ectopic breast to further comprehend the characteristics of this rare disease.  Clinicians and pathologists should always consider it as a differential diagnosis when presented with a vulvar mass.