Introduction & Objective: The possible link between anxiety disorders, such as social anxiety, and neuropsychological functioning has received much less attention. The present study was set out to investigate the effect of social anxiety on one of the executive performances, that is, shifting function. Also, performance in this function is investigated with regard to processing efficacy and performance effectiveness.

 Materials & Methods: For this purpose, in 2012-2013, 24 patients with social anxiety disorder and 24 non patients in multi-stage sampling method were recruited and tested by clinical in-terview, connor social anxiety scale, self-reported mental effort scale, Wisconsin card sorting test, The results were analyzed with mixed repeated measures, modified bone ferreni post hoc test, and independent T- test.

Results: Under basic and induced anxiety conditions the results showed that there were signifi-cant differences between groups in processing efficacy (P<0.001). But for the performance effectiveness in the basic condition there were significant differences just in two subscales: number of categories completed and the total number of errors. In the induced anxiety condi-tion there were significant differences between groups in all subscales performance effective-ness (P<0.001).

 Conclusion: Working memory in the social phobia patients was impaired, as compared to that of the healthy controls. Working memory deficiency observed in social phobia might be re-lated to assumptions about social phobia cognitive model. This model suggests that individu-als with social phobia cannot shift their attention to external stimuli in social situations.