This paper present the field-measured thermal performance of two atrium building in a clinic center located in Kerman, where winter is cold and dry. The case studies are an enclosed atrium space. The atriums have open corridors at each storey connecting them to adjacent space. The site measurement and monitoring work were carried out for one day covering clear day in November 2010. The weather conditions during the day measuring period were stable and heating system was off. This study will investigated about different temperature of atrium levels with plant and without plant. This study has shown that in cold and clear winter day, when average of external relative humidity in this day was around 9%,in the atrium relative humidity changed between 10%- 22% and total temperature in atrium level were changed between 18'C-28'C. whilst in the atrium without plant this range were between 3%-23% and 15'C-35'C respectively.