Lipomas are the most common benign tumors. Especially, lipomas of the tongue are rare tumors that are represented by less than 0.5% of all benign tumors in oral cavity and only 3 cases were reported in Korea. The etiology and pathogenesis of lipomas are still unknown. Mechanical and inflammatory mechanisms have been discussed. Post-traumatic lipomas are adipose tissue tumor forming at the location of a preceding soft tissue trauma at between 5 months and 6 years after trauma. Post-traumatic lipomas predominantly were represented at the lower extremity and gluteal regions. In contrast, the occurrence of post-traumatic lipomas at the oral cavity were extremely rare. Furthermore, there is no proof of a specific hypothesis of origin. Recently, we experienced a case of post-traumatic lipoma of the tongue. A man who are taking anticoagulants as a treatment of old cerebral infarction was admitted to the our hospital because painless swelling of the both lateral border of tongue for eight month, after a venesection at ventral portion of tongue. Under general anesthesia the tumor was successfully managed it by surgical excision and histological examination showed a lipoma.