According to the DSM-5 dimensional approach and evidence-based assessments classification, the Children’s Florida Obsessive Compulsive Inventory (C-FOCI) is a promising instrument for the dimensional assessment of both the presence of obsessive–compulsive symptoms and their severity in youth. The aim of this study was to evaluate the reliability (internal consistency, and four-week retest), validity (convergent and predictive), and factor structure (confirmatory factor analysis) of a Persian version of the C-FOCI across clinical and community samples of youth. Participating youth (N = 391) from 7–17 years of age included non-referred community youth (n = 329) or youth who met diagnostic criteria for OCD (n = 62). Similar to the original English version of the C-FOCI, the Persian version of the scale demonstrated a two independent factor structure, good convergent and discriminant validity through its correlations with other specific measures of pediatric psychopathology, good reliability in terms of internal consistency and temporal stability, and acceptable sensitivity/specificity for the detection of pediatric OCD caseness. These results suggest sound psychometric properties of the Persian version of the C-FOCI. Findings add to the literature and provide cross cultural support on the utility of C-FOCI as a dimensional measure for assessing both obsessive–compulsive symptoms and their severity in clinical and research settings.