Résumé : The present study investigated whether social anxiety modulates the processing of facial expressions. Event-related potentials were recorded during an oddball task in young adults reporting high or low levels of social anxiety as evaluated by the Liebowitz Social Anxiety Scale. Repeated pictures of faces with a neutral expression were infrequently replaced by pictures of the same face displaying happiness, anger, fear or disgust. For all participants, response latencies were shorter in detecting faces expressing disgust and happiness as compared to fear or anger. Low social anxiety individuals evoked enhanced P1 in response to angry faces as compared to other stimuli while high socially anxious participants displayed enlarged P1 for all emotional stimuli as compared to neutral ones, and general higher amplitudes as compared to non-anxious individuals. Conversely, the face-specific N170 and the task-related decision P3b were not influenced by social anxiety. These results suggest increased pre-attentive detection of facial cues in socially anxious individuals and are discussed within the framework of recent models of anxiety.