A blood ritual is any ritual that involves the intentional release of blood.

A common blood ritual is the blood brother ritual, which is rumored to be Native American in origin. Two people, typically male, cut or poke the pads of their thumbs (or another part of the hand), causing them to bleed, then press the pads of their thumbs to one another's. This ritualizes the two people involved becoming brothers in a symbolic way. Obviously this is an unsafe practice where blood borne pathogens are concerned.

[[ ritual. Though piercing does not always cause bleeding, it certainly can. Piercing has been practiced in a number of indigenous cultures throughout the world, usually as a symbolic rite of passage, a symbolic death and rebirth, an initiation, or for reasons of magical protection.

Blood rituals often involve a symbolic death and rebirth, as literal bodily birth involves bleeding. Blood is typically seen as very powerful, and sometimes as unclean. Blood sacrifice is sometimes considered by the practitioners of prayer, ritual magic, and spell casting to intensify the power of such activities. The Native American sundance is usually accompanied by blood sacrifice.

Some blood rituals involve two or more parties cutting themselves or each other followed by consumption of blood. The participants may regard the release or consumption of blood as producing energy (not physical energy, but rather energy in a mystical sense) useful as a sexual, healing, or mental stimulus.