en عمومى General پژوهشي Research <span style="font-size:11pt"><span style="line-height:107%"><span style="font-family:Calibri,sans-serif"><b>Background and purpose:</b> Chronic illness separates children from their normal living environment and intermittent, and hospitalization causes them to feel frustrated and hopeless. Since playing has a significant role in reducing children&#39;s negative emotions, this study was conducted to investigate the effect of play therapy on the frustration and hopelessness of children with chronic diseases.</span></span></span><br> <span style="font-size:11pt"><span style="line-height:107%"><span style="font-family:Calibri,sans-serif"><b>Materials and methods:</b> This is a semi-experimental study with two control and intervention groups. A total of 60 children with chronic diseases hospitalized in 6 departments of Children&#39;s Medical Center in Tehran were selected by convenience sampling method to participate in this study based on the entry criteria (n=30 in the intervention and n=30 people in the control group). A demographic information form and Kazdin&#39;s hopelessness scale in children (HSC) were used to collect the data, and SPSS software version 16 was used to analyze the collected data.</span></span></span><br> <span style="font-size:11pt"><span style="line-height:107%"><span style="font-family:Calibri,sans-serif"><b>Findings:</b> The findings of this study indicated that the play therapy had a significant effect on the hopelessness of children in the intervention group, so that their mean score of hopelessness after the intervention was much lower compared to before intervention (P-value<0.05). The effect size of this intervention on the children hopelessness was 0.215, which is higher than 0.08, indicating the effectiveness of intervention.</span></span></span><br> <span style="font-size:11pt"><span style="line-height:107%"><span style="font-family:Calibri,sans-serif"><b>Conclusion:</b> The results of this study showed that playing has a positive effect on the level of frustration of children with chronic diseases. Therefore, playing is recommended to reduce frustration and improve mental health of children with chronic diseases.</span></span></span><br> &nbsp; Play Therapy, Hopelessness/Frustration, Children, Chronic Disease 136 147 http://intjmi.com/browse.php?a_code=A-10-1-616&slc_lang=en&sid=1 Reyhaneh Khodabakhsh 10031947532846007045 0009-0001-8187-8872 No Msc Of Pediatric Nursing, School Of Nursing& Midwifery, Tehran University Of Medical Sciences, Tehran, Iran. Maryam Shirdel 10031947532846007046 0009-0002-7831-5718 No Msc In NICU Nursing, School Of Nursing And Midwifery, Tehran University Of Medical Sciences, Tehran, Iran. Akram Sadat Sadat Hoseini 10031947532846007047 10031947532846007047 No Professor Of Tehran University Of Medical Sciences,Tehran, Iran. Najmeh Tavakol 10031947532846007048 10031947532846007048 No Ms Of Biostatistic, Poursina Hakim Digestive Diseases Research Center, Isfahan University Of Medical Sciences, Isfahan, Iran. Jamalodin Begjani 10031947532846007049 10031947532846007049 Yes Associate Professor, Tehran University Of Medical Sciences, Tehran, Iran.