Increased interest in alternative approach to thoractomy has developed because of the considerable morbidity associated with the standard posterolateral thoracotomy[ST]. Muscle sparing thoracotomy is appeared as excellent alternative because of less postoperative pain and morbidity than standard posterolateral one. Vertical axillary muscle sparing thoracotomy[VM] is the newly revised modified muscle sparing thoracotomy that overcomes the disadvantages of previous lateral muscle sparing thoracotomy such as seroma, cosmetic problems, and need of subcutaneous drains. We conducted a prospective study of 45 consecutive patients to compare postoperative pain, muscle strength of serratus anterior and latissimus dorsi, and range of motion of the shoulder girdle between ST and VM group. There were no difference in preoperative status, surgical procedure, morbidity, mortality and hospital stay between two groups. But there were significant less postoperative narcotics requirements, more preserved latissimus dorsi and serratus anterior muscle strength, nd larger range of motion of shoulder girdle [ especially flexion and internal rotation in VM group. The opening time was prolonged[p<0.01] but closing time was less in VM group [p<0.01]. The sum of opening and closing time was not different in two group. The length of incision line was shorter in VM group. The vertical skin incision was concealed by the upper arm.In conclusion vertical axillary muscle sparing thoracotomy is good alternative for various intrathoracic procedures with less postoperative pain, well preserved muscle strength,increased range of motion of the shoulder girdle and impressive cosmetic outcome.