Background: The mediastinum is the anatomic space which is restricted and the clinical aspect varies according to location, size and type of neoplasm. Diagnostic and therapeutic approaches to mediastinal neoplasms have changed over and over. We presented our recent therapeutic experiences with these neoplasms. The object and method: The 36 patients were treated in operation from 2000 until 2006. The male patients were 20 and the female patients were 16. Age of the patients ranged from 5 to 70, and the median age was $46.4{pm}21.9$. The child patients were two. Result: The most prevalent anatomic distribution of the neoplasm was anterosuperior mediastinum. The most common neoplasm was thymoma, followed by thymic cyst, teratoma, ganglioneuroma. The complete excison of neoplasm was accomplished in 96% of patient group except thymoma patient group. One patient underwent total thymectomy, and the other 12 patients underwent extended thymectomy from 13 thymoma patient group. In the malignant neoplasm, 7 patients were received additional treatment after operation. There was short-term death of 1 person and late death of 1 person. Conclusion: Our results except clinical manifestation are compared favorably with other reports. Surgery is the management of choice for patients with mediastinal neoplasm and early curative resection is considered to optimize clinical outcome for patients.