BACKGROUND: The general anesthesia for endoscopic sinus surgery (ESS) is associated with increase in intraoperative bleeding, which can interfere with optimal visualization through the endoscope, so we compared the effectiveness of propofol as induced hypotensive agent with sodium nitroprusside (SNP) in ESS. METHODS: Twenty patients undergoing ESS under general anesthesia were allogated randomly to recieve thiopental sodium induction with enflurane maintenance and induced hypotension by SNP (SNP group), or propofol induction and propofol maintenance (propofol group). The two groups were recieved nalbuphine, vecuronium, nitrous oxide and oxygen for anesthesia. The hypotensive effects, hemodynamic changes were evaluated with mean arterial pressure (MAP), heart rate (HR), hematocrit of preoperative, intraoperative and postoperative period and estimated blood loss (EBL). RESULTS: Mean arterial pressure was significantly decreased during hypotensive anesthesia (p<0.05), but any other parameters (HR, EBL and hematocrit change) were not significantly different in two groups. CONCLUSION: Propofol has an effectiveness of hypotensive agent as SNP; and make endoscopic sinus surgery technically easier and safer by improving endoscopic visualization of the surgical field with less blood loss.