Abstract: Objective :To approach the diagnosis, surgical treatment and curative effect of giant mediastinal tumor. Methods :The clinical findings of 14 patients withant mediastinal tumor were analyzed retrospectively. Results :Nine of the cases wire male and 5 wire female. 10 cases with benign and 4 cases with malignant tumor. The size of tumor ranged from 15x12x10 cm to 25x20x15 cm, and the average of the tumors was 15 cm in diameter. Of the cases 9 underwent complete resection and 5 palliative resection of the tumor. Two cases with postoperative respiratory failure and one with acute pulmonary edema following thoracotomy recovered finally without peri-operative death. The results of postoperative follow- up were as follows: 10 patients with benign tumor still survived during 6 months to 8 years, one of malignant cases survived for 7 years, and the others with malignancy died from local recurrence or distant mediastasis. Conclusions :Surgical treatment is one of the reasonable choices for the giant mediastinal tumor, according to the study. The technique of the segmental resection or enblock resection is available and more attention to pay for avoiding heavy bleeding and re-expanding pulmonary edema. A proper postoperative chemo- radiotherapy might be helpful to those with malignant tumor who underwent palliative surgery.