Façade planting is an innovative idea to make use of plants in cooling the surrounding. Double Skin Green Façade is a type of green walls that offers psychological benefit in addition to its thermal performance. The aim of this research was to define the effect of Double Skin Green Façade on indoor thermal conditions. Orientation and cavity width were the parameters identified in this research in order to achieve maximum efficiency. A Double Skin Green Façade model was applied on an office building to investigate its thermal performance in Cairo, using Design Builder software. The simulation process was divided into three phases. The first phase aimed to define the day with extreme high temperature among the year to undergo further phases. The second phase intended to compare the performance of the green façade to that of the base case in south, east, and west orientations. Then the cavity width parameter was examined on third phase. Results showed improvement on indoor air temperature after applying Double Skin Green Façade. Moreover, the research recommended its application on the west orientation with 1.5 meters cavity width with respect to Cairo climatic conditions.