People with antagonistic personality traits are reportedly more racist, sexist, and xenophobic than their non-antagonistic counterparts. In the present studies (N1 = 718; N2 = 267), we examined whether people with antagonistic personality traits are also more likely to hold homophobic and transphobic attitudes, and, if they are, whether this can be explained by their moral intuitions. We found that people high in Machiavellianism, narcissism, and psychopathy are more likely to endorse homophobic and transphobic views. The associations of Machiavellianism and psychopathy with homophobia and transphobia were primarily explained by low endorsement of individualizing moral foundations (i.e., care and fairness), while the association of narcissism with these beliefs was primarily explained by high endorsement of the binding moral foundations (i.e., loyalty, authority, and sanctity). These findings provide insight into the types of people who harbour homophobic and transphobic attitudes and how differences in moral dispositions contribute to their LGBTQ+ prejudice.