Purification is the process of rendering something pure, i.e. clean of foreign elements and/or pollution, and may refer to:
- List of purification methods in chemistry
- Water purification
- Organisms used in water purification
- Purification of quantum state in quantum mechanics, especially quantum information
- Purification theorem in game theory and economics, a Nash equilibrium consisting of randomly mixed strategies
- Ritual purification, the religious activity to remove uncleanliness
- Purification of the Virgin, a Christian liturgical feast
- Purification Rundown in Scientology, a procedure that supposedly rids the body of toxins
- Purification, a 2002 Crimson Thorn album
- Sweat lodge