Aim: The aim of the present study to assessment of Hypertonic Saline and Mannitol on Intraoperative Brain Relaxation in Patients with Raised Intracranial Pressure undergone Supratentorial Tumors Resection. Methods: A prospective randomized double blind study was conducted in the Upgraded Department of Paediatrics, Patna Medical College and Hospital, Patna, Bihar, India, for 7 months. 100 patients with American Society of Anesthesiologists physical statuses I–III and aged 20–61 years with clinical or radiological evidence of raised ICP, scheduled to undergo supratentorial tumor resection were included in the study. 100 patients randomized into two equal groups. Each patient was administered 5 ml/kg of either 20% mannitol or 3% HTS over 15 minutes (min) after skin incision. Hemodynamic data, brain relaxation and serum electrolyte levels were recorded. Results: Intraoperative brain relaxation was comparable between the two groups. There was a statistically significant difference in the mean arterial pressures (MAPs) between the two groups after one minutes (min) with a greater degree of decrease in blood pressure recorded in the mannitol group (P = 0.037). MAP with mannitol was significantly lower than the preinduction value after 75 min of administration of drug (P = 0.002). Urine output was significantly higher in the mannitol group (P = 0.00). Administration of HTS was associated with a transient increase in serum sodium concentrations, which wasstatistically significant but returned to normal within 48 h (P < 0.001). Conclusions: We concluded that both mannitol and HTS provided adequate intraoperative brain relaxation. On the contrary, there was no statistically significant fall in blood pressure with HTS. Thus, we advocate the use of HTS over mannitol as it maintains better hemodynamic stability.