We introduce a new inventory measuring sex-based harassment intentions and threat perceptions grounded in gender status threat theories (Berdahl, 2007; Stephan et al., 2016). In Study 1 (N = 568 men), an initial Sex-Based Harassment Inventory (SBHI) was developed with 12 scenarios depicting gender status threats to which respondents rated the likelihood to engage in gender harassment, unwanted sexual attention, supportive conduct, and their perceptions of threat. The final version of the SBHI contained six scenarios with four items each. Gender harassment and unwanted sexual attention intentions loaded on a single, reliable factor, labeled harassment intentions. Two other factors measured threat perceptions and supportive behavior intentions. harassment intentions correlated significantly with threat perceptions, likelihood to sexually harass (Pryor, 1987), hostile and benevolent sexism (Glick & Fiske, 1996), and masculine identification (Glick et al., 2015). In Study 2 (N = 391 men), a non-threat version of the SBHI was compared to the threat version. Threat perceptions mediated the effect of scenario version on harassment intentions, which was stronger at moderate to high levels of hostile sexism and social dominance orientation. Consistent with Berdahl’s theory, these studies present promising initial evidence for the validity of the final version of the SBHI and the links between gender status threat and sex-based harassment intentions to gender status threat.