A 36-year-old man presented with a hard mass on the right forearm. He had no specific symptom, but wanted surgical excision for cosmetic purpose. On the physical examination, the mass was located on the ulnar side of forearm, presented mild tenderness. Ultrasound examination showed a hypoechoic mass, 1.3×1 cm mass in the subcutaneous tissues. Under the local anesthesia, the patient underwent an excisional biopsy of the lesion. The histopathology and the immunohistochemical analysis confirmed the tumor to be a glomus tumor. The extradigital glomus tumors are sparsely reported apart from pain. The patients can present with subcutaneous nodule, or with discoloration of the skin. These atypical symptoms make difficult to diagnose extradigital glomus tumors. In the current study, we report the case of a patient with asymptomatic glomus tumor in a extradigital lesion of forearm.