Mastocytosis is a rare skin condition which typically manifests with or without accompanied systemic symptoms. Localized tissue mastocytosis is known as mastocytoma. A Mastocytoma localized to the vulva is an extremely rare condition only a few known cases of this condition have been reported so far. Due to the scarcity of this ailment no consensus about the diagnosis, management and treatment has been reached. In this case, we reported a 23-year-old female patient with a mastocytoma that had been growing for 18 years.