Tampering may refer to:
- Tampering (crime), intentional modification of products in a way that would make them harmful to the consumer
- Tampering (sport), the practice, often illegal, of professional sports teams negotiating with athletes of other teams
- Tampering (quality control), changing an industrial process in an attempt to improve output but having the opposite effect
- Tamper-evident, a device or process that makes unauthorised access to a protected object easily detected
- Tamper resistant making it difficult to tamper with an object or system
- Tamperproofing, The belief that something cannot be tampered with
- Sabotage, modification of a device to induce failure
- Witness tampering, an illegal attempt to coerce witnesses called to testify in a legal proceeding