Normative social influence is a type of social influence that leads to conformity. It is defined in social psychology as "...the influence of other people that leads us to conform in order to be liked and accepted by them." The power of normative social influence stems from the human identity as a social being, with a need for companionship and association.

Normative social influence involves a change in behaviour that is deemed necessary in order to fit in a particular group. The need for a positive relationship with the people around leads us to conformity. This fact often leads to people exhibiting public compliance—but not necessarily private acceptance—of the group's social norms in order to be accepted by the group. Social norms refers to the unwritten rules that govern social behavior. These are customary standards for behavior that are widely shared by members of a culture.

In many cases, normative social influence serves to promote social cohesion. When a majority of group members conform to social norms, the group generally becomes more stable. This stability translates into social cohesion, which allows group members to work together toward a common understanding, or "good," but also has the unintended impact of making the group members less individualistic.