Introduction:The main symptoms of carpal tunnel syndrome are pain, numbness, and paresthesia in the thumb and second and third fingers along the area innervated by the median nerve. In this study, we observed and reported changes in median nerve thickness through ultrasound after acupotomy treatment. Methods: One patient who received acupotomy treatment for the treatment of carpal tunnel syndrome from June 29, 2022 to August 20, 2022. Results: The patient's symptoms were similar until the end of treatment, but on ultrasound images, the thickness of the median nerve in the distal carpal tunnel decreased from 0.4 cm on June 29, when the patient first visited the hospital, to 0.33 cm on July 16. During the subsequent 4 treatments, all of them remained constant at 0.28 cm, resulting in a final decrease of 42%. Conclusion: Improvement of median nerve thickness was observed after applying acupotomy treatment for CTS.