Introduction: The present study aimed to examine the effectiveness of a multi-sessions of Cognitive Bias Modification for Attention (CBM-A) program on reducing the attentional bias to threat and social anxiety symptoms in a population of socially anxious individuals.
 Materials and Methods: The statistical population of this clinical trial included all students with social anxiety disorder aged 18-30 who were referred to faculty of psychology clinic of Ferdowsi University of Mashhad in the 2011-12 academic years. Volunteers with a high score on the Conner’s Social Phobia Inventory (n=30) were randomly assigned into an experimental and a placebo group. At pre-test, participants completed a computerized attentional bias test and Conner’s Social Phobia Inventory. Participants in the experimental group received four sessions of cognitive bias modification training for attentional biases (CBM-A) over 4 weeks for 4 sessions. Placebo group received identical numbers of training sessions with experimental group. At post-test (1 week after training) and 12 weeks follow-up (90 days), all participants also completed the measures of visual attentional biases and social anxiety. The data were analyzed using SPSS version 16 and MANCOVA test.
 Results: According to results the experimental group showed significant reductions in their attentional bias to threat than the placebo group at post-test (P<0.01) and follow-up (P<0.01) assessments. These results indicate participants in the experiment group reported significantly less social anxiety symptoms than those in the placebo group at both post-test (P<0.05) and 12 weeks follow-up (P<0.01).  
 Conclusion: It seems that using a multi-session Cognitive Bias Modification for Attention (CBM-A) program for facilitating disengagement attention from threat may have clinical implications in the treatment of social anxiety.