Background and objectives: The success of functional endoscopic sinus surgery (FESS) depends on visual clarity of the surgical field, which is under studied. Controlled hypotension has many advantages for FESS including reduction in blood loss and improved quality of the surgical field. This study determined whether the use of β-blockers as a premedication could improve the operative field in FESS. Methods: 60 patients aged from 18-50 years, undergoing septoplasty, and FESS were included in this prospective, randomized, double-blinded, placebo-controlled study. Patients were randomly assigned to receive either metoprolol (100mg, group 1) or a placebo (a vitamin tablet, group 2) 60 minutes before surgery. Results: The average blood loss and surgery duration were not significantly higher in the placebo group. The surgical field was graded using Fromme-Boezaart scale and it was significantly clearer(p<0.001) in metoprolol group. The mean arterial blood pressure was significantly lower in the metoprolol group after 30 minutes of induction till the end of surgery (p<0.001). The heart rate was also significantly lower (p<0.001) in those who received metoprolol from before induction of anesthesia up to the end of surgery. Conclusion: metoprolol significantly improves visual clarity and hemodynamics during FESS. Conclusion: metoprolol significantly improves visual clarity and hemodynamics during FESS