The development of osteoma in soft tissues without a direct contact with the adjacent osseous and articular structures is a very rare event. The involvement of the hand is even rarer, with only two previous cases reported so far. A 25-year-old man presented with a painless solid mass in the thenar region of his right palm, which appeared almost 2 years ago and showed a progressive enlargement in the last months. Under regional anesthesia an excisional biopsy was performed and the histopathological evaluation of the lesion confirmed the diagnosis of soft tissue osteoma. The postoperative follow-up period was uneventful without any complication or recurrence. Following a brief period of hand physiotherapy the patient has returned to normal daily activities.