Leiomyomas represent about 3.8% of all benign soft tissue tumors. Vulvar localization is very rare. We present a case of a vulvar leiomyoma and discuss diagnostic and therapeutic features of this disease. A 30-year-old female patient with no medical history, had a 5cm mass located in the left large lip causing a discomfort at the perineum especially in sitting and walking. She underwent a complete surgical excision of the mass. The pathological examination confirmed the diagnosis of a leiomyoma. There was no recurrence after 24-months' follow-up. The vulvar leiomyoma is a rare benign tumor. The diagnosis is made only postoperatively after resection of the mass. The treatment is essentially based on total excision of the mass with a good prognosis.