Osteoma is a common benign bone tumor, usually occurring inside the frontal sinuses and the mandible. The size of the lesion is usually small. It may induce sinusitis if it occurs inside the paranasal sinus. Extraskeletal osteoma is rare in soft tissue. A 67-year-old man presented with a lesion on the palm of his right hand; the lesion had been present for more than 10 years. Radiograph and magnetic resonance imaging of his hand provided adequate information for a differential diagnosis of extra-skeletal osteoma to be made before operation. The tumor was completely resected. Pathology confirmed extra-skeletal osteoma. To the best of our knowledge, this is the first case of extraskeletal osteoma of hand.