Objectives : The aim of this study was to assess the validity and reliability of the Persian version of the Conners’ Adult Attention-Deficit/Hyperactivity Disorder (ADHD) Screening Scale (screening form-self reporting). Method: The Persian version of the scale was produced through translation to Persian, back-translation and confirming the accuracy of translation. The face and content validities of translated scale were checked by four child and adolescent psychiatrists. Afterwards, 100 parents of children with ADHD were chosen using convenience sampling method. Interview with these people was performed by a child and adolescent psychiatrist. The results of interviews for detecting affection with adult’s ADHD based on Utah criteria were compared with the results of Persian version of the Conners’ Adult ADHD Screening Scale, and criterion validity was calculated. For assessment of the test-retest reliability, 30 individuals from the participants completed the scale once more after three weeks. The data were analyzed using Pearson’s and Spearman’s correlation coefficients. Results: The mean age of the studied population was 36 (SD=5) of whom 67% were women. Intraclass correlation coefficients (ICC) for all subscales was higher than 0.7. The Cronbach’s alpha coefficient for all subscales was also higher than 0.8. The Pearson’s correlation matrix of subscales was significant (p<0.01). Also, correlation matrix of items was suitable to each other. Based on the psychiatrists’ clinical interview, 27 parents were diagnosed as having adult ADHD. In assessment of criterion validity, sensitivity and specificity of cut-off point (t score=65) were 59% and 92%, respectively, and for cut-off point of 55, sensitivity and specificity were 89% and 68%, respectively. Conclusion: By changing cut-off point from 65 to 55, the validity and reliability of the Conners’ Adult ADHD Screening Scale (screening form-self reporting) become partially suitable for Iranian population, nonetheless, its specificity criterion is not suitable.