Background and Aims: Induced hypotension reduces blood loss during functional endoscopic sinus surgery (FESS), provides better surgical field visibility and minimizes the incidence of major complications. We aimed at comparing nitroglycerine (NTG) and dexmedetomidine for inducing controlled hypotension in patients undergoing FESS. Material and Methods: Sixty adult patients of ASA physical status I or II, undergoing FESS under general anaesthesia were randomly allocated to two groups of 30 patients each. Group N received NTG infusion at the rate of 0.5-5 mcg/kg/min while Group D patients received a loading dose of Dexmedetomidine 1mcg/kg/min followed by an infusion at the rate of 0.2-0.7 mcg/kg/hr. The infusions were titrated to maintain mean arterial pressure (MAP) in the range of 65-75 mm Hg in both the groups. The visibility of surgical field was assessed by the surgeon using Average Category Scale (ACS) scores. The haemodynamic parameters, rescue fentanyl usage, emergence time and time to first postoperative analgesic request were recorded. Results: The desired MAP (65- 75mm Hg) could be achieved in both the groups. No significant intergroup differences were observed in ACS scores. The mean heart rate was significantly lower in Group D at various time intervals (P<0.05). Rescue fentanyl usage was significantly lower in Group D. Emergence time was significantly lower in Group N. Time to first analgesic request was significantly longer in Group D. Conclusion: Dexmedetomidine is comparable to Nitroglycerine for inducing controlled hypotension in FESS and provides good operative field visibility. Dexmedetomidine has the added advantage of reducing perioperative analgesic requirements.