The purpose of this study is to investigate the effectiveness of teaching philosophy to children on the psychological flexibility of male elementary school students in Marivan. This paper is a quasi-experimental study with a pretest-posttest design with a control group conducted with the aim of applying the results. The statistical population included all elementary school students in the city of Marivan during the 2017-2018 academic year. Using the available sampling method, 50 male students were selected and divided into two experimental and control groups. The participants answered the Acceptance and Action Questionnaire (AAQ-II) before and after the training. 17 45-minute sessions (one session per week) Philosophy for Children (p4c) were presented using native language stories. The educational package included stories selected from the narratives of Iranian authors such as Rumi, Saadi, etc. The collected data were analyzed using SPSS 21 software and analysis of covariance. The results of covariance analysis showed that Philosophy for Children program was effective in influencing students’ psychological flexibility. Overall, according to the results, it can be said that Philosophy for Children education enhances students’ psychological flexibility by strengthening discussion and challenging students’ thinking.