Dog ownership in Iran differs greatly from the United States and Europe. To evaluate the behavioral traits of dogs in Iran, we used a standardized questionnaire, the Canine behavioral Assessment and Research Questionnaire (C-BARQ). We conducted factor analysis on data collected using a Farsi (Persian) translation of the C-BARQ completed by the owners of 223 dogs attending veterinary clinics with their dogs. Nine factors were extracted comprising 49 items that accounted for 68.4% of the common variance. Extracted factors were similar to the original version, although some differences were observed. This modified Persian version of C-BARQ may represent an effective tool for evaluating the behavior of dogs in Iran.