The evidence base concerning the relationship between loneliness and the perception of facial cues of emotion remains mixed. This study further examined the categorisation accuracy, and perceived emotional intensity and emotional valence of facial expressions of emotion in adults displaying high, medium, and low levels of loneliness, whilst controlling for symptoms of insomnia anxiety and depression. Using the University of California Loneliness Scale, participants were stratified into those experiencing high (N = 83), medium (N = 97), and low levels (N = 93) of loneliness. Observing facial expressions of emotion from the Karolinska Directed Emotional Faces database, participants were assessed on their categorisation accuracy and ratings of emotional intensity and valence. After controlling for comorbid psychiatric symptoms, the experience of loneliness was characterised by: positively valanced ratings of angry and sad faces; difficulties in the identification of, and blunted ratings of emotional intensity and valance of happy faces. The outcomes present psychosocial implications for individuals experiencing loneliness.