Objective To analyze the influence of topographic anatomy on brachial plexus block anesthesia, and to provide reference for clinical research and application.  Methods Total of 20 cadavers were selected and located through the modified method  of inferior brachial plexus block of the coracoid process. The nerve blocking points were marked with blue dye, and the nerve concentration sites and marking points were dissected and exposed at the same time. The anatomical relationship between nerve concentration points and body surface markers were explored.  Results The distances from the upper margin of the left centralization to the midpoint of the subclavian border, the inferior margin of the sternoclavicular joint, the shoulder peak and the inferior edge of the coracoid process were (3.62±0.24) cm, (10.39±0.25) cm, (6.67±0.18) cm and (2.80±0.19) cm, respectively. The distances from the upper edge of the right centralization to the midpoint of the subclavian border, the inferior margin of the sternoclavicular joint, the shoulder peak and the inferior edge of the coracoid process were (4.24±0.27) cm, (11.10±0.28) cm, (6.35±0.19) cm and (3.03±0.15) cm, respectively.  Conclusion The application of anatomy improves the accuracy of brachial plexus block, thus improves the effect of brachial plexus block anesthesia, and provides a powerful reference for clinical research and application.