Faces provide a lot of information about people, and people can form impressions of others based on looking at their faces for a short time. Emotions, such as anger, can be conveyed by facial expressions. The facial width-to-height ratio is the ratio between the bizygomatic width of the face and the height between the lips and the eyelids. Previous studies have shown that there may be an association between the facial width-to-height ratio and certain behaviours. For instance, some studies have shown that individuals with high facial width-to-height ratios are more threatening than individuals with low facial width-to-height ratios. This study investigated the possible association between the facial width-to-height ratio and threat. In addition, the facial expression of anger was studied. The method used was electroencephalography conducted on 23 participants most of whom were students at the University of Skövde. More specifically, it was the event-related potential late positive potential that was studied. In addition, the participants’ perceptions of threat were investigated with a rating task questionnaire. Repeated-measures ANOVAs were conducted on the results, and no significant effect of the facial width-to-height ratio on the late positive potential was found. However, it was found that the facial expressions of faces significantly affected the late component of the late positive potential. The questionnaires also indicated that only the facial expressions, and not the facial width-to-height ratio, affected the threat perceived from faces. These results indicate that the facial width-to-height ratio may not be associated with threat.