Background: Video-Assisted Thoracic Surgery can be performed with the lung collapsed. During the procedure, pleural adhesion may result in lung injury, bleeding, and thoracotomy conversion. Identifying the presence of pleural adhesion before surgery can make it easy to plan trocar introduction and perform the procedure. Material and Method: Between June 2009 and November 2009, we performed ultrasound in 24 patients to detect pleural adhesion before surgery and compared the results with the operative findings. We primarily examined the lateral chest, where the trocar would be inserted, and, occasionally, the anterior or posterior chest. Result: Patient diseases were: 6 hyperhidroses, 8 interstitial lung diseases, 5 lung cancers, 2 mediastinal tumors, 1 peripheral pulmonary embolism, 1 metastatic lung cancer, and 1 sarcoidosis. Of the 22 patients who did not have pleural adhesions on ultrasound, four revealed mild adhesions not related to the trocar insertion sites. However, ultrasound showed pleural adhesions in two patients, consistent with the operative findings. There was no air leak or thoracotomy conversion related with trocar insertion. Conclusion: Ultrasound requires only a few minutes to detect the presence of the pleural adhesion and was very useful in identifying the pleural adhesion before VATS.