Abstract: Exposure to distressing computer-generated stimuli and feedback of physiological changes during exposure have been effective in the treatment of anxiety disorders (e.g., social phobia). Here we studied voluntary facial activations as a method for regulating more spontaneous physiological changes during virtual social stimulation. Twenty-four participants with a low or high level of social anxiety activated either the corrugator supercilii (used in frowning) or the zygomaticus major (used in smiling) facial muscle to keep a female or a male computer character walking towards them. The more socially anxious participants had a higher level of skin conductance throughout the trials as compared to less anxious participants. Within both groups, short-term skin conductance responses were enhanced both during and after facial activations; and corrugator supercilii activations facilitated longer term electrodermal relaxation. Zygomaticus major activations had opposite effects on subjective emotional ratings of the less and the more socially anxious. In sum, voluntary facial activations were effective in regulating emotional arousal during virtual social exposure. Corrugator supercilii activation was found an especially promising method for facilitating autonomic relaxation.