Introduction:– Transurethral resection of prostate and bladder tumours are routinely performed procedures. Spinal anaesthesia is the most routinely used procedure for transurethral resection of prostate (TURP). Bupivacaine, has high potency, slow onset and long duration of action is commonly employed for spinal anaesthesia. Small doses of Dexmedetomidine used in combination with bupivacaine, has been shown to produce a shorter onset of motor block and a prolongation in the duration of motor and sensory block with preserved hemodynamic stability and lack of sedation. Our study plans to compare the characteristics of spinal block, haemodynamic changes and total analgesia requirements, following administration of intrathecal 5μg Dexmedetomidine combined with a low dose of 7.5mg of 0.5% hyperbaric bupivacaine versus a higher dose of 10 mg of 0.5% hyperbaric bupivacaine in patients undergoing TURP. Material and methods:– This study was conducted at Govt Medical College and Associate group of Hospitals, Kota from june.2019 to jan.2020. We conducted a Hospital based Randomized double blind controlled observational study of 60 adult cases of both sex. We divided the cases into 2 groups of 30 each, as Group A: Patients was received 10mg (2ml) of 0.5% hyperbaric bupivacaine. Group B: Patients was received 7.5mg (1.5ml) of 0.5% hyperbaric bupivacaine + 5µg Dexmedetomidine (1 ml of Dexmedetomidine diluted to 10 ml with normal saline then 0.5 ml is taken in insulin syringe and added in 7.5mg of 0.5% hypebaric bupivacaine) intrathecally. Standard protocol followed to administering spinal anaesthesia. All data were collected and analysed with the help of suitable statistical parameters. Results:– Our study results in that Dexmedetomidine intrathecally with hyperbaric bupivacaine significantly prolongs duration of sensory and motor blockade and duration of analgesia in TURP surgery.