The effects of acute stress in the innate immunity have been the subject of several studies in the field of psychoneuroimmunology, nonetheless, there is limited experimental data reporting consistent results, particularly in certain psychiatric populations, as with social anxiety disorder. This study investigated how acute stress induced by public speaking influenced innate immunity parameters in this population. The results revealed that, in spite of significant psychological profiles and interpretations of the experimental situation, persons with or without social phobia did not differ much in terms of their immune response, instead, differences in immune response seemed to be related to gender in the conditions of this experiment, which may be related to the carachteristics of the sample. A discussion about the reasons for this differences and mechanisms involved is presented, however, much remains to be studied before conclusions are reached and practical results can be implemented.