Organizing hematoma is a rare benign tumor and it occurs in many location of the body including the brain, spinal cord, neck, maxillary sinus, and parapharyngeal space. Organizing hematoma often occurs in patients who have any previous trauma, operation, or coagulopathy. Even though the locations of organizing hematoma are different, organizing hematomas have similar pathologic findings include hematoma, fibrosis, neovascularization and no evidence of malignancy. Recently, we have experienced a case of slow growing organizing hematoma of the neck. A patient was 70 year-old woman with a mass of the right supraclavicular area over the past 18 years. After the mass excision, the histopathologic examination revealed a organizing hematoma. We report this case with the literature review.