This study was executed under the premise that office public space was the physical realization of the public interest and the amenity of public space could be calculated with a quantitative analysis. The main aim of this study was to make and applicate an amenity indicator of office exterior public space. To achieve those, this study was executed like these. First, the concept and role of amenity, users and exterior public place was studied with literatures. Second, the amenity factors and the elements were extracted and the case studies were investigated. The purposes of the case studies were to check the problems of extracted factors of amenity. Third, the amenity indicator was completed after experts' questionaries and revising the amenity factors. Fourth, the amenity indicator was applied to measure the amenity of public spaces in Teheran-Ro.