Labeling theory is an approach in the sociology of deviance that focuses on the ways in which the agents of social control attach stigmatizing stereotypes to particular groups, and the ways in which the stigmatized change their behavior once labeled.

Labeling theory states that people come to identify and behave in ways that reflect how others label them. This theory is most commonly associated with the sociology of crime since labeling someone unlawfully deviant can lead to poor conduct.

Labeling theory posits that self-identity and the behavior of individuals may be determined or influenced by the terms used to describe or classify them. It is associated with the concepts of self-fulfilling prophecy and stereotyping.