Background: Brachial plexus block is a popular approach for upper limb surgeries and emerging as alternative to general anesthesia due to lesser complications. Brachial plexus block is effective in terms of cost and performance, margin of safety, along with good postoperative analgesia. The local anesthetics were commonly used to produce the regional anesthesia but many studies have proved that addition of other drugs produces synergistic effects. Aims: Aim of this study was to assess the effects of addition of dexamethasone as adjuvant to ropivacaine on postoperative analgesia. Materials and methods: A randomized controlled prospective double-blind study was undertaken involving 60 patients of both sex exposed for upper limb surgeries under brachial plexus block. These patients were randomly divided into 2 groups as Control group: Group R: Would receive 30ml, ropivacaine 0.5%+ 1.5 ml (0.9%) saline (placebo). Study group: Group D: Would receive 30ml of mixture of ropivacaine 0.5%and +1.5 ml dexamethasone(4mg/ml). Results: A randomized prospective placebo controlled double blind study was taken up in two groups of thirty patients each. The mean age of patients was 37.73±10.64years and 34.67±9.75years in ropivacaine and ropivacaine – dexamethasone groups respectively. Majority of them belonged to below 50 years age group. The two groups were comparable with respect to age. The mean time of onset of sensory block in ropivacaine group was 21.00±3.32 minutes and 13.83±5.20 minutes in ropivacaine – dexamethasone group which was statistically significant. The mean time of onset of motor block in this study in ropivacaine group was 28.83±2.15 minutes and the mean onset of motor block in ropivacaine – dexamethasone group was 22.17±4.68 minutes. The difference was statistically significant. The mean duration of postoperative analgesia in ropivacaine group was 15.92±3.53hours and in ropivacaine-dexamethasone group was 20.84±3.13 hours. There was statistically significant difference between ropivacaine and ropivacaine- dexamethasone groups. The mean rescue analgesic doses were lower in ropivacaine- dexamethasone group compared to ropivacaine group. Conclusion: Dexamethasone being a potent corticosteroid it has beneficial effect on addition as a local anesthetic in terms of postoperative pain and requirement of rescue analgesic.