A comparative analysis of the legal systems within European Union countries and relevant regional and international conventions aimed at regulatory harmonization is warranted, given the extensive use of agency, particularly in commercial sectors both domestically and internationally, the varying laws and regulations across different nations, and the discrepancies in Iran's domestic legal framework. This study seeks to address pertinent legal issues and ambiguities by juxtaposing the Iranian legal system with those of the aforementioned countries, particularly in contexts involving international agency dimensions.