The branching sites of dorsal cutaneous branch of the ulnar nerve (DCBUN) from the ulnar nerve proper in the forearm have been described. To demonstrate the precise branching point, we dissected 28 upper extremities of 14 cadavers. The mean value of this point proximal to the styloid process was 87mm: The mean value of the fascicular separation was 217mm. We also confirmed that DCBUN is positioned more either toward medial epicondyle or olecranon to the ulnar nerve proper in the ulnar groove. DCBUN with this anatomic arrangement at the elbow may be less vulnerable to injury or compression than the fascicles of ulnar nerve proper which innervate the palm side of medial two digits and the hand intrinsic muscles. Therefore, understanding the anatomy of DCBUN may be helpful in the electrodiagnostic and surgical procedures: 1, This sensory branch may be used as a donor on an anastomosis of other nerve injuries; 2, Iatrogenic injury of this nerve due to diagnostic and surgical procedures such as arthroscopy at the wrist is preventable.