This study aimed to investigate the effect of verbal self-instructional training on reduction of verbal aggression in educable mentally retarded adolescent boys in Isfahan. The research method w experimental (pretest-posttest with a control group). For this purpose, 20 educable mentally retarded adolescent boys with verbal aggression who were studying in 2012-2013 were selected via available sampling method, and were randomly divided into two experimental and control groups. The experimental group received verbal self-instructional training in ten 45-minute sessions, but the control group received no training in this regard. The research data were collected based on the responses of the subjects’ parents to verbal aggression scale through adolescent behavioral classification project (ABCP) inventory and three month later the follow-up test was administered. The results of covariance analysis test showed that there was a significant relationship between verbal self-instructional training and verbal aggression reduction (p<0.0001). The results of follow-up test showed that the effect had survived even after three months. Therefore, it can be concluded that verbal self-instructional training can have a relatively stable effect on the reduction of verbal aggression in educable mentally retarded adolescent boys.
