Man 62-years-old as for the case. In 2019, he was diagnosed with right hypopharyngeal cancer, and esophageal melanosis was noted on upper gastrointestinal endoscopy before treatment. We did a follow-up upper gastrointestinal endoscopy every year. At a follow-up upper gastrointestinal endoscopy performed in February 2021, he was histologically diagnosed with an esophageal primary malignant melanoma. Computed tomography showed no metastatic lesions. He underwent esophagectomy. He is currently being followed on an outpatient basis and has had no recurrence. Careful follow-up for esophageal melanocytosis is important for early diagnosis of esophageal primary malignant melanoma.