This chapter focuses on the stigmatization of trans men. First, the Trans Men Stigma Scale is examined. Second, Norm-Centered Stigma Theory (NCST) is utilized to explore the relationships among the Trans Men Stigma Scale, the Hetero-cis-normativity Scale (HCN Scale), gender, sexuality, additional gender/sexuality, race/ethnicity, and basic needs. Third, trans men’s experiences with gender- and sexuality-based discrimination, harassment, and violence (DHV) are investigated. In line with the three tenets and hypotheses derived from NCST, there are six patterns found in this chapter: (1) sex-act related stigma is a driving force in the stigmatization of trans men for both hetero-cis and LGBTQ people—however, discomfort with trans men’s sex acts with both men and women are most concerning for hetero-cis people while the stigmatizing beliefs that trans men are too hypersexual and unfaithful are most concerning for LGBTQ people; (2) for both hetero-cis and LGBTQ people, there is strong support for the stigmatizing belief that trans men are not masculine enough; (3) hetero-cis-normativity is positively related to trans men stigma for both subsamples—however, the interaction effects between the HCN Scale and social power axes that moderate these relationships differ for the hetero-cis and LGBTQ subsamples. In addition, there are more significant interaction effects between the HCN Scale and social power axes for the hetero-cis subsample than there are for the LGBTQ subsample; (4) individual social power axes are significantly related to trans men stigma for both subsamples—however, the interaction effects between the social power axes only moderate these relationships for the LGBTQ subsample; (5) trans men experience high levels of gender- and sexuality-based DHV in comparison to the all men subsample and are significantly more likely to experience gender-based discrimination and violence than both the LGBTQ and men subsamples; and (6) being a trans man is significantly related to the likelihood of gender-based DHV but being a trans man is not significantly related to the likelihood of sexuality-based DHV.