Fibroma of the tendon sheath (FTS) is a rare benign tumour that usually develops in the upper extremity, particularly in the fingers, hands and wrists. Herein, we present the case of a patient with an unusually localised FTS compressing the superficial branch of the radial nerve. A 62-year-old woman presented with a superficial radial nerve compression due to FTS of the brachioradialis. Histopathological diagnosis was confirmed as a FTS after marginal excision. The patient who had compression-related symptoms in the superficial branch of the radial nerve recovered completely at one month after surgery. One year later, the patient remained free of symptoms and no recurrence was observed.