Adolescents whose perceived gender expression does not conform to societal expectations may be at greater risk for peer victimization. Prior theorizing indicates the interaction between youth's perceived sex and gender expression may expose them to greater degrees of peer victimization, as predominant patriarchal standards of gender may cultivate higher levels of vulnerability by sex. However, these associations have yet to be empirically examined. Using pooled Youth Risk Behavior Surveillance data from 2013 to 2021 (n = 158,698), we examined the moderating effect of sex on the association between perceived gender expression nonconformity (PGENC) and two types of peer victimization: bullying and cyberbullying. A series of four multivariable logistic regression models examined the association between PGENC and each peer victimization outcome variable. Results demonstrated direct associations between bullying and PGENC (aOR = 1.20) and between cyberbullying and PGENC (aOR = 1.10). PGENC adolescents accumulated greater risk for bullying and cyberbullying than adolescents whose gender expression matches their reported sex. PGENC males, compared to PGENC females, experience greater degrees of bullying (aOR = 1.33) and cyberbullying (aOR = 1.24). Findings indicate peer victimization may asymmetrically target youth based on gender expectations ascribed to their sex and on the broader hegemonic patriarchal values that privilege masculinity and devalue femininity.