This study examined the effectiveness of training based on the Pygmalion effect on cognitive confusion and extra-role behaviors among first-grade primary school teachers in Meybod City. A quantitative, quasi-experimental pretest-posttest design with a control group was employed. The statistical population comprised all first-grade primary school teachers in Meybod, from whom 30 participants were selected using convenience sampling and randomly assigned to either an experimental group (n = 15) or a control group (n = 15). Participants completed Organ’s (1988) Extra-Role Behaviors Questionnaire and Mason’s (1995) Cognitive Confusion Questionnaire. The experimental group received eight 60minute sessions of the Pygmalion effect training program (based on Jacobson & Rosenthal, 1986), while the control group received no intervention. After the intervention, both groups completed the same questionnaires again. Data were analyzed using analysis of covariance (ANCOVA) with SPSS26 at a significance level of 0.05. The results showed that the training based on the Pygmalion effect had a significant effect on cognitive confusion and extra-role behaviors in the teachers of the first grade of primary school in Meybod City (P<0.001). Based on the findings, it can be concluded that by teaching the Pygmalion effect to teachers, it is possible to reduce their inefficient behaviors and cognitive confusion, and also make them more efficient in the workplace and classroom so that they show more extra-role behaviors. The results showed that Pygmalioneffectbased training had a significant positive effect on reducing cognitive confusion and increasing extra-role behaviors in the experimental group compared to the control group (p < 0.001). It can be concluded that equipping teachers with knowledge of the Pygmalion effect can decrease their inefficient cognitive patterns and enhance their engagement in extra-role behaviors, thereby improving their effectiveness in both classroom and school environments.