Performing a brachial plexus block is very useful for shoulder arthroscopic surgery. Several techniques for blocking the brachial plexus have been described with the purpose of improving the efficacy and minimizing the risk. The parascalene approach was introduced in 1979. This block approaches at the lateral border of the anterior scalene muscle and superior to the clavicle. At this level, the incidences of phrenic nerve paralysis and spinal or epidural anesthesia should be minimized. Previous studies have reported on ultrasound-assisted brachial plexus blocks, but few studies have applied this imaging technology to the parascalene region. We report here on 8 cases of parascalene brachial plexus block with using ultrasound guidance to show the clinical usefulness of this technology for conducting arthroscopic shoulder surgery. Ultrasound technology is valuable to anesthesiologists to localize nerves and the needle placement during the parascalene approach to block the brachial plexus for conducting arthroscopic shoulder surgery.