A 66-year-old Japanese man was admitted to our hospital, presenting with massive hematemesis. Emergency endoscopy revealed a bleeding tumor at the esophagogastric junction. The endoscopic appearance of the tumor was that of a Borrmann 2-like tumor, with a brownish-black discoloration. Bioptic histology confirmed the diagnosis of malignant melanoma. Atypical melanocytes with junctional changes were also found at a small pigmented patch in the lower esophagus, separate from the gross tumor. Melanocytosis was noted in the adjacent esophageal epithelium in the resection specimen following surgery. No primary lesion was found elsewhere, even in the patient's skin. These pathologic findings support the possibility of multicentric occurrence of malignant melanoma in esophageal melanocytosis. The patient is alive 11 months later, with multiple liver metastases. Massive hematemesis is an unusual presentation of primary malignant melanoma of the esophagus.