Malignant melanoma is predominantly a skin disease but in rare instances it may occur at other sites. A vaginal melanoma is a rare clinical entity and the round cell type is an uncommon variant. Although the present case was clinically diagnosed as a urethral caruncle, on histopathological examination and immunostaining it was diagnosed as a round cell pigmented malignant melanoma. The patient refused radical surgery and was given a full course radiotherapy treatment but died a year later. Malignant vaginal melanoma carries a very poor prognosis even when lesion is localised at the time of presentation. The five-year survival rate ranges from 10–20% with the prognosis being influenced by tumour size. A tumour size ≥3cm has a poor prognosis. Age, mitotic count, stage, and location of the lesion do not influence survival rates.