Competition and cooperation are pervasive across diverse domains of human society, and outcome feedback in these contexts has been shown to significantly influence human emotional responses and behavioral strategies. However, there is limited understanding of the mechanisms through which outcome feedback in obstructive and supportive settings affects the perception of facial expressions of interactors. To address this issue, thirty-seven participants in this event-related potential (ERP) study completed a modified version of the Tetris game with randomly assigned interactors (cooperative supporter, competitive hinderer). After receiving outcome feedback (correct, incorrect), participants were asked to rate the valence of surprised faces which were assumed to be displayed by interactors. Behaviorally, surprised faces in supportive correct feedback contexts were rated as more pleasant, while those in obstructive correct feedback contexts were rated as less pleasant. The ERP results showed a significant main effect of outcome feedback on the FRN and LPPfeedback, with enhanced amplitudes for incorrect relative to correct trials. More importantly, face-related P1, N170, and EPN components showed significant interactions between interaction type and outcome feedback. Surprised faces in obstructive correct contexts evoked larger P1 amplitudes compared to those faces in obstructive incorrect contexts. Conversely, amplified N170 and EPN responses were observed for faces in supportive correct contexts compared to those in supportive incorrect contexts. For the LPPface, an amplified response to faces was observed in correct feedback contexts compared to incorrect ones, irrespective of the influence of interaction type. Altogether, these findings offer the first empirical evidence that feedback cues in obstructive and supportive contexts can interactively influence the top-down processing of facial expressions, shifting attention away from the suppression of aversive stimuli towards a focus on self-related positive information, thus providing insights into the neurocognitive mechanisms underlying the impact of complex social information on higher-order cognitive processes.