Aims and objectives: To observe the effect of dexamethasone on onset and duration of anaesthesia, when used as an adjuvant to bupivacaine in supraclavicular brachial plexus block. Aim of the study is to evaluate the effects of 0.5% Bupivacaine and 0.5% Bupivacaine with dexamethasone in supraclavicular brachial plexus block by comparing the onset and duration of sensory and motor blockade, hemodynamic variables and number of rescue analgesics required. Materials and methods: Following approval by institutional ethical committee, 60 patients posted for elective upper limb surgeries were included and divided into two groups. Group A received 30ml of 0.5% Bupivacaine with 2ml of 0.9% NaCl and group B received a mixture of 30ml of 0.5% Bupivacaine and 2ml of Dexamethasone (8mg). The required parameters were observed and analyzed. Results: The onset of sensory and motor block was early in Bupivacaine–Dexamethasone group compared with bupivacaine alone. The duration of Sensory and motor block was prolonged with Bupivacaine–Dexamethasone group compared with Bupivacaine alone. The number of rescue analgesics were less in Bupivacaine– Dexamethasone group.