Domed roofs have been used in Iran and many other countries to cover large buildings such as mosques, shrines, churches, schools, etc. However their favorable thermal performance made them to be employed in other buildings such as bazaars, or market places, in Iran. The aim of this study was to determine the air pressure distribution over domed roofs, employing a numerical method. In this investigation, a three-dimensional model and a laminar inlet air flow were considered. The k-ε RNG method was employed for the turbulent flow simulation method. Simulation was run under three conditions of windows and a hole on top of the dome being open, or closed. The results were compared with the results obtained by an experimental investigation of the same domed-roof model. The results of this research can be employed to determine the heat transfer coefficient of wind blowing on domed roofs and the passive cooling effect of such structures.