Arthroscopic knee surgery is routinely performed these days for various indications none the less with pain in post operative period requiring analgesic cover. Pain is mediated through Opiate receptors in intraarticular tissue. Dexmedetomidine, a alpha (α) 2 adrenergic agonist whose administration Intra articularly along with Inj. Ropivacaine (local anesthetic) does helps in providing good analgesia postoperatively. With this background this comparative we planned study between inj. ropivacaine and ropivacaine with dexmedetomidine deposited intra articularly for post operative analgesia in arthroscopic knee surgery. Duration of analgesia, efficacy of drugs and any side effects between both groups were compared. Fifty patients undergoing elective arthroscopy surgery of knee joint of ASA grade II & III; 18-65 years of age of either sex were included and after the surgery was over, they were randomly divided in two groups of 25; Group A (n=25) to receive Inj. Ropivacaine 0.25% and Group B (n=25) to receive Inj. Ropivacaine (0.25%) + Inj. Dexmedetomidine (1 µg/kg) making final volume 20 ml pushed intra-articularly under aseptic precautions by the operating surgeon. Patients were observed postoperatively for Pulse, RR, Temp, BP, Sedation using Modified Wilson Score and Pain assesment at rest using VAS every 2 hourly for first postoperative day. Rescue analgesic using Inj. Diclofenac sodium 75 mg IV was given at VAS score was ≥ 4. The duration (in hours) for first dose of analgesic was considerably more in group B [2.68 ± 0.48] than group A [1.88 ± 0.34]. There were no significant postoperative complications in both groups. So mixing of Intraarticular Dexmedetomidine with Ropivacaine provides longer duration of analgesia and reduced pain scores as compared to Intraarticular Ropivacaine alone safely.