There are a lot of mosques which have panel radiators for heating purposes since this method is very common in Turkey. In this study, the effect of the efficiency of panel radiators, which are used for heating mosque, was investigated numerically using the STAR CCM+ software. The 3D mosque model which has a 20x20 m floor area and 29.5 m dome height is used for modelling. The temperatures of the radiators are kept at 60 °C. The temperature distribution is investigated at the end of 1 and 1.5 hours. The heating of the volume of space in which worship takes place, which is less than ~2 m in height, can be achieved after the other volume is heated. Given that the heating takes a long time, there are large differences in temperature between these volumes. Therefore, this study has proved numerically that the use of radiators for heating of mosque in heating of mosques of a large internal volume is absolutely unsuitable.