Aim: To compare the efficacy of and safety of dexmeditomidine versus nitroglycerine during hypotensive anaesthesia induced by either drug in adult patients posted for elective spine surgeries. Material and methods: This was a prospective, randomized, and double blinded clinical comparative study conducted in the Department of Anaesthesiology Jawaharlal Nehru medical college and hospital Bhagalpur, Bihar, India from July 2018 to February 2019. 80 participants belonging to ASA class I or I between 20 and 55 years of age scheduled for elective spine surgeries were include in this study. The study drug dexmeditomidine was given to group DX in the dose of 1 micro gram/kg body weight in a 600 seconds infusion before induction diluted to 10 ml with normal saline followed by maintenance dose at infusion rate of 0.2- 0.7 micro gm/kg. The group NG received 10 ml plain normal saline over 600 seconds before induction followed by maintenance dose of nitroglycerine at an infusion rate of 0.5-10 micro gm/kg/min. different parameter were compared in both the groups. Results: The basal heart rates are comparable between the two groups and the difference is not statistically significant. There is a statistically significant difference between the two groups after starting loading dose infusion and induction, where in statistically significant fall in HR is noted in group DX. But after laryngoscopy and intubation there is increase in heart rate in both groups which more in group NG compared to group DX (p<0.001). The intraoperative mean HR during surgery is significantly lower in group DX compared to group NG(p<0.001). At 15 min minutes there is no significant difference in the 2 groups with respect to the average surgical field grading of each study population. At 30 min there is significant difference between 2 groups with group DX having average surgical field grade of 1.88 ±0.52, which is less compared to that of group NG, 2.54±0.49(p<0.001). The average intraoperative surgical field grade was 2.18±o.51 in group DX, which was significantly better than 2.41±0.61 in group NG (p=0.29). Conclusion: Dexmedetomidine and Nitroglycerine both can be used with great safety profile to achieve controlled hypotension during spine surgeries.