Both abnormal stress and reward responsivity are consistently linked to multiple forms of psychopathology; however, the nature of the associations between stress and reward sensitivity remains poorly understood. The present study examined associations between the HPA axis stress response and event-related potentials sensitive to the receipt of reward-related feedback in a pre-post experimental paradigm. Neural responses were recorded while male participants completed a simple monetary reward guessing task before and after the Montreal Imaging Stress Task. Results demonstrated that acute psychosocial stress significantly reduced the magnitude of neural responses to feedback in the reward-sensitive delta, but not the loss-sensitive theta, frequency band. In addition, a larger delta frequency response to rewards at baseline predicted reduced overall cortisol response in the stress condition. These findings suggest, therefore, that neural reward circuitry may be associated with both risk for and resilience to stress-related psychopathology.