A congenital tumor in the thoracic spinal canal was located ventral to the spinal cord, compressing the spinal cord into the left spinal canal. The patient’s numbness and weakness of both lower extremities progressively worsened before surgery. A hemilateral laminar approach was used to completely remove the tumor on the ventral side and relieve the compression of the spinal cord. At the same time, there was no damage to the left vertebral plate, spinous process, ligaments and left paravertebral muscles, which basically did not interfere with the stability of the spine and truly achieved minimally invasive treatment of intravertebral tumor. After the operation, the patient’s symptoms disappeared, and he wore a brace and walked on the ground the next day.