BACKGROUND: Benign and malignant brain tumors have different histopathological characteristics, including different degrees of tissue infiltration and inflammatory response. The aim of this retrospective study was to compare the incidence of postoperative nausea between the two categories of brain tumors in patients undergoing awake craniotomy. METHODS: After IRB approval, we retrospectively extracted data from perioperative records between January 2005 and December 2010. Patients were divided based on the postoperative histopathological diagnosis into two groups, benign and malignant. The incidence of nausea, rescue anti-emetics, pain scores and postoperative analgesic requirements were compared between the two groups up to 12 hours postoperatively. Intraoperative anti-emetic, anesthetic, and analgesic regimens were also assessed. Limitations of this study include the retrospective design, the arbitrary dichotomization of tumors as benign or malignant, and the inability to gather accurate data regarding vomiting from the medical record. RESULTS: Data from 415 patients were available for analysis, with 115 patients in the benign group and 300 patients in the malignant tumor group. A higher postoperative mean pain score was found in the benign brain tumor group compared to the malignant brain tumor group (P < 0.05). However, there was no difference in the incidence of nausea between the two groups. CONCLUSION: The different histopathological characteristics of brain tumors have no association with postoperative nausea in patients undergoing awake craniotomy. Patients with benign brain tumors experience more pain than patients with malignant brain tumors. This difference in postoperative pain may be due to the younger age of the patients in the benign group.