Widespread access to and use of pornography has led to concern about the potentially negative effects of exposure to pornography on emerging adults—its largest user group. Past research shows that salient social norms can influence subsequent behavior. This study, therefore, explored the relationship between salient pornography-related norms and pornography use among emerging adults, as well as the relationship between parental mediation of pornography during adolescence and emerging adults’ salient pornography-related norms. Results revealed that emerging adults are more likely to view pornography when they hold a salient belief (norm) that their peers both approve of viewing and regularly view pornography. The study also found that parents’ provision of rules about viewing pornography during adolescence may reduce future pornography use by instilling the salient belief that the parent disapproves of viewing pornography. These findings suggest that the effect of rules in the home about adolescents’ use of pornography may persist into emerging adulthood.