Objectives: This study aims to evaluate the cultural adaptation, validity and reliability of the Persian version of Experience of Caregiving Inventory (ECI) in families of patients with severe mental disorders. Method: After the translation and cultural adaptation of ECI, 225 family members of patients with severe mental disorders completed the ECI, the General Health Questionnaire (GHQ-28) and a demographic questionnaire. The Split half test was used to assess reliability. To determine internal consistency, Cronbach’s alpha test and the concurrent validity was calculated by Pearson’s correlation between the GHQ-28 and the ECI total negative score. Results: Reliability of the Inventory as assessed by the Spearman-Brown correlation coefficient was 0.80. The range of the Cronbach’s alpha for each subscale, total negative score and total positive score was 0.51 to 0.90. Pearson’s correlation between the GHQ-28 score and the total negative score was 0.37 (p<0.01).  Conclusion:  The Persian version of the ECI has good reliability and validity for family members of patients with severe mental disorders.