Myofibroma is a benign tumor composed of fibroblasts and myofibroblasts, occasionally occurring most commonly as a solitary lesion of soft tissue, skin, or bone in children younger than 3 years of age. Solitary lesion of myofibroma is exceedingly rare in adult jaws. This report describes a rare case of myofibroma in the mandible that occurred in a 41-year-old Korean woman.