In sociology a social rule refers to any social convention commonly adhered to in a society. These rules are not written in law or otherwise formalized.

In social constructionism there is a great focus on social rules. It is argued that these rules are socially constructed, that is created by society. By created by society it is meant that these rules act upon every member of a society, but at the same time, are re-produced by the individuals.

Sociologists representing symbolic interactionism argue that social rules are created through the interaction between the members of a society. The focus on active interaction highlights the fluid, shifting character of social rules. These are specific to the social context, in particular time and space. That means a social rule changes over time within the same society. What was acceptable in the past may no longer be the case. Similarly, rules differ across space: what is acceptable in one society may not be so in another.

Social rules reflect what is acceptable or normal behaviour in any situation. Michel Foucault's concept of discourse is closely related to social rules as it offers a possible explanation how these rules are shaped and change.

It is the social rules that tell people what is normal behaviour for any specific category. Thus, social rules tell a woman how to behave in a womanly manner, and a man, how to be manly.

There are conflicting theories on how social rules are established, as well as on how they come to change.