Intraneural ganglia in the upper extremity are rare, and the involvement of the digital nerve of hand has not been reported. The following case report demonstrates a 57-year-old woman with a symptomatic nodular mass on the thenar area of the left hand. Magnetic resonance images showed a lobulated, homogeneous mass of high signal intensity on T2-weighted images and low signal intensity with peripheral enhancement on T1-weighted images. Excisional biopsy and histopathologic examination revealed an intraneural ganglion of the digital nerve of the thumb. Her symptom disappeared immediately after the surgery, and has remained free of abnormal sensation and parestheia for the 3-year follow-up period.