The decision whether or not to preserve orbital contents during surgical resection of malignant tumors involving the sinonasal tract and the orbit has been an issue of controversy. The purpose of the study was to examine the oncological and functional outcomes of multimodality therapy for patients with advanced maxillary cancer that invaded the orbit.Retrospective study was conducted using medical records of 55 patients who underwent primary surgical management with or without orbital exentration for maxillary cancer abutting or eroding orbit.Among 55 cases of maxillary cancer, 26 patients (26/55, 47%) were suspected to be invaded orbit in pre-operative radiologic studies. During surgery, 11 patients (11/26, 42%) had the tumor close to periosteum without definite involvement and six patients (6/26, 23%) had the tumor with periosteum involvement in frozen biopsy. These 17 patients (17/26, 63%) underwent maxillectomy without orbital exentration. And nine patients (9/26, 35%) had the tumor with orbital fat or muscle involvement in frozen biopsy and received orbital exentration. 19%(5/26) of the patients had local recurrence. There were no statistically significant differences in recurrence rates (18% vs 22%) and 5-year disease free survival rate (55% vs 34%) between orbit preservation group and orbital exentration group. In 11 patients (11/26, 42%), discrepancy between pre-operative radiologic studies and pathologic reports were found.Control of the primary site and functional results are important in the curative treatment of maxillary cancer. Orbital preservation procedure during radical maxillectomy for the patients without definite orbital fat or muscle invasion must be considered carefully. And proper pre-operative evaluation and frozen biopsy during surgery for orbital invasion is essential because of the high false positive rate of pre-operative radiologic studies for orbital invasion.