Experiences of transthoracic approaches to the thoracic cord lesions were reported. Since 1983, we have performed six transthoracic approaches to the thoracic lesions; one thoracic OPLL, one dumbbell-shaped neurinoma, two thoracic soft disc, one epidural metastatic tumor to thoracic vertebrae. From the viewpoint of surgical anatomy, the thoracic vertebrae show a physiological kyphosis and the subarachnoid space of the ventral site is narrower than that of the dorsal site. Due to such anatomical characteristics, the thoracic laminectomy for decompression is not so effective as in the cervical or lumbar region and a relatively small mass lesion can bring a paraplegic state. The lesion of the ventral site of the thoracic cord has been regarded as no man's land because of poor results of posterior approaches. Instead of posterior approaches, anterior or anterolateral approaches with transthoracic route have been adopted. In the present paper, we used transthoracic anterolateral approaches for four patients and anterior sternum-splitting approach for two patients. The operative procedures of the approaches were described in detail. By these approaches, we could treat four patients with favourable results but the result of thoracic OPLL was poor. The cause of this poor result seemed to depend upon the intraoperative compression of the thoracic cord. For the troublesome complication, we described the postoperative cerebrospinal fluid leakage into thoracic cavity with respiratory disturbance. Several devices to prevent such troublesome complication were discussed.