Background: The brachial plexus block has been shown to be an effective way to provide anesthesia for upper limb surgeries.The supraclavicular approach is the most widely used technique due to its ease of usage and effectiveness. The infraclavicular block usually results in a near complete blockade and provides stability for catheter placement.A high frequency linear (5-12)MHz probe is used for the block.Use of USG for these blocks has improved effectiveness and reduced complications. Methods: This prospective randomized single blinded study was performed at SKIMS Medical College & Hospital in 118 patients divided into Group S of 59 patients undergoing Supraclavicular block and Group I of 59 patients undergoing Infraclavicular block under Ultrasound guidance. The data regarding following parameters was collected: age,gender,time taken for block,onset of sensory and motor block;andit was analysed using students ttest,Chi-square test and SPSS version 20.0. Results: The average age difference between the two groups was found statistically insignificant.The Gender distribution between the two groups was found comparable with a p-value of 0.712.Average time taken for block in S group was 6.1 min.versus 5.7 min.for I group.Onset of sensory block in group S was 16.1 min. while in group I was 12.6 min. with p-value of <0.001.The onset of motor block in group S was 18.2 min. while in group I it was 17.6 min.The number of patients with adverse events was low more so in I group which was statistically significant. Conclusion: The USG guided Supraclavicular and Infraclavicular blocks are highly effective and safe for upper limb surgeries.