Background:This clinical study was undertaken to compare the effects of intrathecal midazolam and fentanyl as additives to intrathecal bupivacaine 0.5 % for spinal anaesthesia. Materials and Methods: This prospective, randomized, comparative study was conducted on 100 adult patients of ASA physical status 1 & 2 in the age group of 18 years to 60 years, at MAMATA GENERAL HOSPITAL, KHAMMAM. on patients admitted for elective surgery from the period october 2017 - september 2019. Patients belonging to Group A received 3 ml (15 mg) of hyperbaric bupivacaine (0.5 %) + 0.2 ml (1 mg) of preservative free midazolam + 0.3 ml of normal saline and Group B received 3 ml (15 mg) of hyperbaric bupivacaine (0.5 %) + 0.5 ml (25 μg) of fentanyl. Patients were preloaded with intravenous Ringer’s lactate solution 15 ml / kg just before administering subarachnoid block. Subarachnoid block was administered in L3-L4 intervertebral space with 25G Quincke’s needle. Standard monitoring was carried out in the form of pulse oximetry, ECG and non-invasive arterial blood pressure monitoring