Decisions to pursue risky sexual encounters, despite the clear potential negative consequences, have long intrigued researchers. A host of explanations have been proposed (e.g., the effects of sexual arousal and/or substance intoxication on decision-making, an imbalance between excitatory and inhibitory mechanisms in sexual response). However, the role of working memory capacity in sexual decision-making has received relatively little attention. The current study investigated whether working memory capacity (WMC) moderates the relationship between arousal and sexual aggression. Fifty-nine male volunteers viewed 20 consensual and 20 non-consensual images of heterosexual interaction while their physiological arousal levels were recorded using skin conductance response. Participants also completed an assessment of working memory capacity, Towse's Sentence Completion Task (Towse, Hitch, & Hutton, 2000) and a date-rape analogue task (developed by Bernat, Calhoun, & Adams, 1999) for which they had to identify the point at which an average Australian male would cease all sexual advances in response to verbal and/or physical resistance from a female partner. Participants who were more aroused by and spent more time viewing the non-consensual sexual imagery nominated significantly later stopping points on the date-rape analogue task. Consistent with our predictions, the relationship between arousal and nominated stopping point was strongest for participants with lower working memory capacity. For participants with high working memory capacity, arousal was unrelated to nominated stopping point. Results of the current study support the role of working memory capacity as a moderator of the relationship between arousal and sexual decision-making/behavior. Deficits in working memory capacity have been shown to be related to other types of dysregulated behavior (e.g., problematic alcohol use, aggression), suggesting that problems with attentional control make it challenging for individuals to both look beyond immediate rewards and gratification and to consider the often very real likelihood of significant negative outcomes in the future. This may be especially true with stimuli that are highly salient and very rewarding (e.g., sex), leaving these individuals vulnerable to engaging in sexually risky behavior. Future research could explore further whether high working memory capacity may serve as a protective factor by directing decision-making toward less risky behavior even when a person is highly aroused. Results should be replicated on clinical populations. Limitations and additional future directions are discussed.