AbstractThe ultrastructure of nerve endings in the human prostate was studied using glutaraldehyde‐OsO4and KMnO4fixation. The nerve endings were classified into three categories according to the size of the vesicles and the contents of the synaptic profiles. In addition to the conventional adrenergic and cholinergic axons, a third type of axon profile containing a predominance of large granular vesicles was constantly found. Synaptic contacts were found only on smooth muscle cells. No epithelial innervation could be demonstrated. The functions and possible transmitters of the various types of axon terminals are discusse