Members of stereotyped groups are vigilant to situational cues signaling threats to their social identity. In one psychophysiological experiment, we examined whether mere exposure to a watching male face would increase attentional vigilance among female STEM students due to the activation of math-gender stereotypes. Male and female students performed an alleged math intelligence task while being primed with male faces or control images. Automatic responses to errors were captured with error-related negativity (ERN), a neural index of error vigilance. Women showed larger ERN upon making errors when primed with male faces compared to control images, whereas no such priming effect occurred among men. Moreover, this face priming effect was pronounced only among women highly invested in pursuing STEM careers. These findings suggest that minimalistic social cues may activate negative stereotypes early in informational processing, thereby selectively shunting attention on errors in stereotype-relevant tasks among individuals invested in the performance domain.