A 40-year-old male patient was admitted with complaints of right shoulder pain and decreased range of motion for two days. He was diagnosed with axillary web syndrome. Palpable subcutaneous cord which extended from axillary crease down to the ipsilateral arm was revealed. He was administered a non-steroidal anti-inflammatory drug and arranged 15 sessions of physical therapy. To the best of our knowledge, this is the first case to be reported in the literature without any known etiology, and we call attention of clinicians to this syndrome.