The impacts of point source height and 13 kinds of window configuration on the indoor air quality of isolated building,adopting natural ventilation,were studied by the way of numerical simulation.The results show the indoor concentration is lower with the source on the ground than with the source located as high as one half of the building height.The influence of the window configuration on the indoor concentration should be considered combinedly with the height of the source,at the same time the configuration of the window would significantly affect the dimensionless ventilation rate and particularly the window on the upper part of the windward wall would obtain a higher ventilation rate.