Abstract: In this study, a polystyrene-brick composite wall, which is composited with the polystyrene-brick filled with concrete, soil and concrete board, was developed to be the north wall of the Chinese solar greenhouse (hereafter referred to as “solar greenhouse”).The purpose of this study is to investigate the heat insulation and storage performances of the polystyrene-brick composite wall and to analyze the feasibility of substituting for the clay-brick sandwich wall.The tested solar greenhouse was located in Yongqing county, Langfang city, Hebei province(116°35′ E, 39°18′ N).It was 80 m long and 10 m wide.The north wall was the polystyrene-brick composite wall composited with 24cm polystyrene-brick filled with concrete, 45 cm soil and 5 cm concrete board in the direction from exterior to interior.The polystyrene-brick, which was made with polystyrene, was 24 cm wide with a 12 cm-wide cavity.The test period was from Dec.20, 2013 to Jan.30, 2014.During the period, the tested solar greenhouse was used to growing zucchini and employed drop irrigation.The heat insulation sheet was rolled up and down at 8:00 and 16:30, respectively.The wind vent would be open if the indoor air temperature was high during daytime.The indoor and outdoor air temperatures, solar irradiating on the inner surface of the wall, the inner surface temperature and soil temperature in the wall were measured.The data collected in a typical cloudy day (from Dec.25, 2013, 8:00 to Dec.26, 2013, 8:00) and a typical sunny day (from Dec.28, 2013 8:00 to Dec.29, 2013, 8:00) were used to analyze the heat performances of the polystyrene-brick wall.Then, the inner surface temperature of a clay-brick sandwich wall, which was composited with 24 cm clay-brick, 10 cm polystyrene board and 24 cm clay-brick, was simulated with one-dimension differential model to analyze the feasibility of substituting for the clay-brick sandwich wall.During the period when the solar greenhouse was covered with heat insulation sheet, the inner surface temperature of the polystyrene-brick composite wall was (2.5±0.2)℃ and (5.4±1.4)℃ higher than the indoor air temperature in the cloudy day and the sunny day, respectively.It is indicated that the heat released by the wall into the solar greenhouse during the nighttime of the sunny day was 2.1 times than that during the nighttime of the cloudy day.As a result, the indoor air temperatures in the nights of cloudy day and sunny day could be maintained at (9.8±1.1)℃ and (13.0±2.1)℃, which were (15.1±2.0)℃ and (22.6±1.1)℃ than the outdoor air temperature , respectively.The results meant that the solar greenhouse can meet the requirement of most crops.According to the simulated and measured results, the differences in the inner surface temperature between the clay-brick sandwich wall and the polystyrene-brick composite wall were less than 0.3 ℃.On the other hand, the heat release region of the polystyrene-brick composite wall in the cloudy day and sunny day was 17 cm and 33 cm, respectively, and both were smaller than the thickness of soil and concrete board.It is indicated that the thickness of soil and concrete was large enough for storing heat in the daytime.Besides, the heat resistance of the polystyrene-brick filled with concrete was estimated as 2.93 m2 K/W.It was two times of the lowest heat resistance of the wall in local solar greenhouse.Thus the heat resistance of the polystyrene-brick composite wall was large enough to prevent heat in the soil from flowing to the outside.Finally, it is concluded that the polystyrene-brick composite wall is feasible to be the north wall of the solar greenhouse and feasible to substitute the polystyrene-brick composite wall for the clay-brick composite wall.