The relationship between the housing arrangement, adjacent building interval and the average ventilation ratio which is a location indicator of ventilation is analyzed intended for modeled residential district. The difference of ventilation ratio between windward and leeward side houses which is occurred in the case of aligned arrangement, is reduced when the adjacent building interval increases or it becomes a staggered arrangement. In the real housing estates, characteristics of the ventilation ratio are generally consistent with the calculation results in the modeled residential district, since the housing arrangement pattern is similar to the modeled residential district. However, the ventilation ratio may change greatly due to a slight difference of open space and building form in the neighborhood. Local impact by the housing arrangement and district characteristics is also necessary to be taken into account.