Surgery of the skull base region has been regarded impossible because of its difficult access and the complex anatomical structures. Recently, however, brand-new radiographic diagnostic methods as well as development of medical instruments and surgical techniques enabled the accurate localization of tumor and an application of surgical treatment. And the angiographic intervention provides more precise information about the vascular supply of the tumor and appropriate preoperative management which made the main procedure much easier and of little danger. But, when the skull base tumor involves the internal carotid artery(ICA), not only a complete removal of tumor but the surgical approach will be difficult. So, how to manage the ICA properly will be an imperative factor for the surgeon to establish a surgical modality. The authors reviewed 12 cases of tumor involving the ICA at the skull base region which were treated surgically. The problems related with the management of ICA were analyzed with case reports and our standard of temporary ICA balloon occlusion was suggested.