Research has implicated reward sensitivity as one potential shared mechanism underlying reactive and proactive aggression. The current study examined the effect of reward sensitivity, assessed multi-modally through a behavioral task and self-report, on the perpetration of reactive and proactive aggression assessed via a laboratory paradigm. Participants were 184 undergraduate men and women. Hierarchical linear regression revealed positive main effect of reward sensitivity on aggression that did not differ according to condition. This finding offers initial evidence for reward sensitivity as a common etiological correlate of reactive and proactive aggression. And supports future research on shared risk factors that could be targeted to reduce both reactive and proactive aggression.