115 10.52547/APSY.2023.229340.1409 Research Article The Effectiveness of Combined Program of Parent Management Training and Mindful Parenting on Parental Stress, Parent-Child Relationship and Child’s Externalizing Problems F. Kosari 1 , P. Sabahi 2* & Sh. Makvand Hosseini 3 1. Ph. D Student in Psychochology, Mahdishahr Faculty of Psychology and Educational Sciences, Semnan University, Semnan, Iran. Email: farzane.kosari@yahoo.com 2. Assistant professor, Department of Psychology, Mahdishahr Faculty of Psychology and Educational Sciences, Semnan University, Semnan, Iran. Email: p_sabahi@semnan.ac.ir 3. Associate professor, Department of Psychology, Mahdishahr Faculty of Psychology and Educational Sciences, Semnan University, Semnan, Iran. Email: shmakvand@semnan.ac.ir Abstract Aim: This research was conducted with the aim of determining the effectiveness of the combined program of parent management training and mindful parenting training on parental stress, parent-child relationship, and child's externalizing problems. Methods: The research was semi- experimental with pre-test, post-test and three-month follow-up with a control group. The population of the current study was made up of all mothers with children aged 4 to 9 years in Semnan city in 1400, from among whom 24 mothers were selected by available sampling method and randomly divided into two experimental and control groups. The experimental group received 16 hours combined program in two hours per week, while the control group was placed on the waiting list. The research tools included Abidin's parenting stress index (1995), Pianta's parent-child relationship scale (1992), and Eyberg's Child Behavior Inventory (1978). Data analysis was done through multivariate covariance analysis with SPSS-23 software. Results: The mentioned program can be effective in reducing parenting stress (p<0/05) and the child's externalized problems (p<0/05), it is also effective in reducing conflicts between parents and children and bringing their relationship closer (p<0/05) but it does not change the degree of dependence between parent and child (p = 0.213), all results were stable in the follow-up phase except the child's externalizing problems (p = 0.573). Conclusion: This combined program can be an effective intervention to reduce parenting stress and improve parent-child relationship. Key words: Parent Management Training, Parental stress, Mindful Parenting Quarterly of Applied Psychology, Vol. 17, No. 2 (66), Summer 2023, 115-139 ISSN: 2008-4331- eISSN: 2645- 3541 Published online: 22 June 2023 Accepted: 9 February 2023 Received in revised form: 4 January 2023 Received: 3 November 2022 Citation: Kosari, F., Sabahi, P., & Makvand Hosseini, Sh. (2023). The Effectiveness of Combined Program of Parent Management Training and Mindful Parenting on Parental Stress, Parent-Child Relationship and Child’s Externalizing Problems. Quarterly of Applied Psychology, 17 (2):115-139.