Abstract: Objective To compare the effect of ultrasound-guided brachial plexus block between the position on the uninjured arm and the supine position. Methods Sixty cases of frozen shoulder undergoing ultrasound-guided brachial plexus block and arthroscopic release in our hospital between March,2014 and August,2015 were enrolled and randomly divided into two groups.The brachial plexus block in Group A was performed with B ultrasound-guided needle by the position on the uninjured arm;while in Group B was performed by the supine position.When the needle point reached the plexus,10 ml drug (0.3% Ropivacaine+0.5 mg Mecobalamin) was injected.The operation time,needle adjustable angle,block efficiency and the probability of complications were compared between the two groups. Results By the position on the uninjured arm,the adjustable angle of needle was significantly increased from (123.4±4.2 vs.28.9±4.6),the operation time was reduced[(4.3±1.8) min vs.(5.2±2.0) min],the difference were statistically significant with 95% possibility.Meanwhile,the block efficiency,lasting time,sensory degree and the probability of complications remained at the same level. Conclusion The ultrasound-guided brachial plexus block from the position on the uninjured arm should increase the needle adjustable angle,shorten the operation time,and maintain the operation success rate and safety,it is more efficient and convenient as compared with the supine position,which suggests that the healthy lateral position holds a promising future of clinical utility.