Abstract: In order to analyze the heat flux variation characteristics of solar greenhouse with brick wall,an experiment was carried out at Tianjin in winter of 2012 to measure the heat flux on ceiling,north wall,and soil.The results show that heat flux variations of the two monitoring points,situated at the north of soil and the top of the back wall,display a single-peak pattern.The heat fluxes of the two monitoring points,situated at the south of soil and the bottom of the back wall,are between 5.0 and 10.0 W·m^-2 for a day.The diurnal variation characteristic of heat flux is especially distinct during the day with sunshine,while the amplitudes of heat flux during the continuous cloudy days is relatively small.The results suggest that soil and wall are the main areas for heat storage and heat release and the ceiling and the combine places of each enclosing structures are the areas for heat release.According to the variation rules of heat flux,the heat preservation performance of greenhouse could be improved for better greenhouse production.