PURPOSE: We examined the success rate and adverse effects of ultrasound-guided axillary and supraclavicular approach brachial plexus block. METHODS: From December 2013 to February 2014, 580 cases of patients received ultrasound-guided axillary approach or supraclavicular approach brachial plexus block. All blocks were performed by one anesthesiologist under ultrasound visualization using 0.2% or 0.75% ropivacaine 1% lidocaine with epinephrine in 1:200,000 as the anesthetic mixture. RESULTS: Failure rate of ultrasound-guided brachial plexus block was 1.2% and 0.2% in axillary and supraclavicular approach, respectively. In supraclavicular approach brachial plexus block, Honer's syndrome was observed in 17.9%, chest discomfort in 14.9%, and arterial puncture in 1%. There was no adverse effect in axillary approach brachial plexus block. CONCLUSION: Ultrasound-guided brachial plexus block serves higher success rate and lower occurrence rate of adverse effect and makes it useful for hand and upper extremity surgery. Supraclavicular approach has relatively higher success rate and lower rate of adverse effect than axillary approach.