In response to the tragically high incidence and negative consequences of female-directed violence in intimate relationships, a large literature has been dedicated to the investigation of the proximate and the ultimate or evolutionary predictors of men's partner-directed violence. Evolutionary psychology offers a framework for investigating the design of evolved information-processing mechanisms that motivate costly behaviors such as men's partner-directed violence. We review several forms of men's partner-directed violence, including insults, sexual coercion, physical violence, and homicide, from an evolutionary psychological perspective and with a particular focus on the adaptive problem of paternity uncertainty. The problem of paternity uncertainty is hypothesized to have selected for the emotion of male sexual jealousy, which in turn motivates men's nonviolent and violent mate retention behaviors. We review empirical evidence for the relationships among paternity uncertainty, male sexual jealousy, and men's partner-directed violence. We propose that a comprehensive understanding of men's partner-directed violence will be achieved only by careful consideration of both proximate and ultimate causes.