Primary oral melanoma is known to be an extremely rare and aggressive neoplasm arising from the mucosal epithelium of the oral cavity especially upper jaw (palate or alveolar gingivae). Malignant melanoma that does not originate in the skin is a very rare disease and is considered one of the most deadly of all human neoplasms. Oral malignant melanoma (OMM) represents about 1% of all melanomas and approximately 0.5% of all oral malignancies. OMM has been reported in patients aged 20 to 80 years and has a male predilection. Because most mucosal melanotic lesions are painless in their early stages, so delayed recognition and subsequent treatment result in worst prognosis. Here, we report three cases with significant heterogeneity in morphological features and biologic behavior.