Objectives: Psychosocial assessment is a crucial step in delivering evidence-based care to both caregivers and children with cancer. The need for tailoring psychosocial interventions for each member of families that struggle with pediatric cancer, increasingly points to the fact that systematic and comprehensive psychosocial screening is very important. The Psychosocial Assessment Tool (PAT 3.1) is a brief parent report screener which is based on Pediatric Preventive Psychosocial Health Model theoretical framework (PPPHM; Clinical, Targeted, and Universal). The present study aimed to validate the PAT for an Iranian sample. Methods: Primary caregivers of 151 children diagnosed with cancer took part in this study and filled in the batteries of questionnaires at Mahak Hospital. Validation scales were used to examine the congruent validity. Results: Among the 8 subscales of the PAT, Social Support (α=0.82), Child problems (α=0.79), Sibling problems (α=0.90), Family problems (α=0.71), and the total score subscale (α=0.88) had strong internal consistency. However, Family beliefs (α=0.64), and Stress reaction (α=0.67) subscales had moderate internal consistency. The lowest internal consistency was related to Family structure/resource subscale (α=0.48). Nearly half of the families tired in Targeted level of psychosocial risks, 29.8 % were tired in Clinical level and 21.2 % were tired in Universal level of psychosocial risks. Conclusions: The results provide support for validity of the Farsi version of the PAT. Farsi PAT is a valid instrument for systematic screening of the psychosocial risks for children with cancer and their family members and delivering psychosocial care consistent with risk.