Proponents of sexual economics theory argue that women exchange sex for men’s resources. This idea is likely to promote a competitive view of gender relationships that undermines gender equality by characterizing women as manipulative and financially dependent on men. Heterosexual college students (N = 474) who were randomly exposed to a popular YouTube video describing sexual economics theory increased their (1) behavioral support for sexual exchange concepts, (2) endorsement of the theory, and (3) adversarial views of heterosexual relationships, compared with a control group of students. Sexual exchange theory endorsement and adversarial heterosexual beliefs positively covaried, and both attitudes were related to participants’ sexism. Reading a critique of sexual exchange theory, that emphasized mutual respect and affection as precursors to heterosexual intimacy, counteracted the consequences of exposure to the theory. The findings provide evidence that disseminating sexual exchange theory via video on the Internet negatively affects young adults’ views of gender relationships. Educators, and others who wish to explore sexual economics theory through the use of this video, should also include a discussion of the countervailing evidence available.