: In the anquity of post-operative analgesia, the inception of α-2 adrenergic agonist agents in subarachnoid space with adjuvance to bupivacaine has opened new chapter. The intent of the study was to compare the onset of duration of sensory and motor block, hemodynamic effects, post-operative analgesia and adverse effects of dexmedetomidine and clonidine with hyperbaric 0.5% bupivacaine for spinal anaesthesia. : Sixty adult patients received subarachnoid block either with Injection Bupivacaine (15mg) with clonidine (30µg) or Injection Bupivacaine (15mg) with Dex medetomidine (10µg). Patients were monitored for variations in heart rate and noninvasive blood pressure after the spinal anaesthesia was given till the surgery got over every 5 minutes. Both the groups were compared for onset time for sensory block, time to reach sensory block to T and T level, time of regression of sensory block by 2 dermatomes and duration of analgesia.: Mean Onset time of sensory block, time to reach T and T level was greater but not significant in Dexmedetomidine group but regression time of sensory block by 2 dermatomes was significantly higher in clonidine group, 100.21±2.58 minutes as compared to 80.43±3.45 in dexmedetomidine group. Onset time to reach bromage II was significantly faster in group BD (35.53 ±3.57seconds) as compared to Clonidine group (49.03 ± 30.15seconds). Dexmedetomidine group patients had significantly (p<0.0001) higher duration of analgesia (589 ± 5.5minutes) as compared to Group clonidine (507 ± 4.8minutes). There was no sedation and no hemodynamic instability observed in either of the groups. We conclude that though both Clonidine and Dexmedetomidine prolongs duration of sensory and motor block of Bupivacaine, But Dexmedetomidine is more appropriate as it provides better VAS score (quality) and longer duration of postoperative analgesia than clonidine.