Mucosal malignant melanoma arising from the head and neck region is a rare entity, and it is more aggressive than cutaneous melanoma. Furthermore, the complexity of the oral cavity makes surgical excision more difficult. Oral malignant melanoma is a rare tumour of melanocytic origin, accounting for 20-30% of malignant melanomas at the mucosal surface and 16% intra-orally. Hard palate and maxillary gingiva are the most common involved sites. The age of reported patients ranges from 20 years to 80 years. Hence, we do hereby present a case of malignant melanoma of mandibular gingiva with review of the literature in a 42-year-old female patient.