Introduction: Accessory breast tissue is a very rare finding in the general population with an incidence of one to two percent. An even rarer occurrence is accessory mammary-like tissue which developed breast carcinoma. The authors present a case of aggressive and metastatic carcinoma of vulvar originating from mammary-like tissue. Case: A 73-year-old Caucasian female presented with a lesion in her left vulva. The lesion was ulcerated and fragile. A dermatologist had evaluated the lesion and took a punch biopsy. Result was vulvar carcinoma. She was admitted to the gynecologic oncology clinic then after and was operated. After a radical vulvectomy and bilateral inguinal lymphadenectomy she received adjuvant radiotherapy because of lymph node metastasis. One year after the finish of radiotherapy patient was found to have lung and femur metastasis. She began to receive systemic chemotherapy for metastasis. Conclusion: Primary mammary-like adenocarcinoma of the vulva is exceedingly rare. There is no consensus about the diagnosis, treatment, and follow up of these patients in literature. However, given that histological data confirms these cancers are behaving like breast cancers instead of known patterns of vulva cancer, the best treatment practices for breast cancer may be applied to treat these vulvar carcinoma patients.