Frenum piercing is a type of body piercing located on the underside of the shaft of the penis. It is a surface piercing, meaning it does not enter the erectile tissue or the urethra, only the skin. As this piercing is normally perpendicular to the penis, several frenal piercings may be done, creating a frenum ladder.

The earliest reference to frenum piercings would be "Die künstlichen Verunstaltungen des Körpers bei den Batta. Zeitschrift fur Ethnologie" 16:217-225 1884. He wrote:

"Amongst the Timorese of Indonesia, the Frenulum beneath the glans penis is pierced with brass rings, the function of the ring is to enhance stimulation during sex."

Contrary to most surface piercings, frenum piercings tend not to reject or migrate much, though this will vary depending on the subject.