Background: Many studies show that, Dexmedetomidine hastens the onset of sensory and motor block, prolongs anaesthesia and analgesia of local anesthetics in various neural blocks. Very few studies are done using Dexmedetomidine in peribulbar block. The objective of the present study was to evaluate the effect of adding Dexmedetomidine to local anesthetics in peribulbar block for patients undergoing cataract surgery. Methods: Forty adult patients, scheduled for cataract surgery were randomly assigned to two equal groups. Group C (Control group) received 2.5 ml each of a mixture of 2% Lidocaine with Adrenaline and 0.5% Bupivacaine plus Hylase 150 i.u., and 0.5ml saline. Group D (Dexmedetomidine group) received 2.5 ml each of a mixture of 2% lidocaine with Adrenaline and 0.5% Bupivacaine plus Hylase 150 i.u and Dexmedetomidine 25 g in 0.5 ml saline. Onset of sensory and motor block, duration of motor block and duration of analgesia was recorded. Pain was graded using the verbal analogue scale and recorded. Hemodynamic, and sedation parameters were recorded perioperatively. Results: Onset of sensory (0.925±0.348 minutes) and motor block (9.5±0.827 minutes) was significantly shorter in group D compared to group C (1.225±0.334 minutes and 11.75±1.70 minutes, being onset of sensory and motor block respectively). Duration of motor block (277±85.75 minutes) and duration of analgesia (408.8±142.456 minutes) was more prolonged in group D than in group C (163.25±46.29 minutes and 171±103.41 minutes, being duration of motor block and duration of analgesia respectively). Both groups were pain free intraoperatively. Sedation score was similar in both groups. Heart rate and blood pressure were maintained around baseline in both groups. Conclusion: Dexmedetomidine (25µg) as an adjuvant to a mixture of Lidocaine and Bupivacaine in peribulbar block hastens the onset of sensory and motor block, prolongs the duration of motor block and analgesia, with no side effects, and is a safe and effective for cataract surgery.