Reduced scale experiments were conducted to investigate the behavior of smoke in cavity like spaces, which are found in buildings. The cavity space model used in the experiments has a square horizontal section of 0.8mx0.8m, and the height of the floor can be changed from 0 to 3m. This paper presents the results for the case where the cavity has no opening at the bottom and the fire source is located at the center on the floor. The heat release rates in this series of experiments ranged from 0.5 to 4kW. The temperatures were measured by the thermocouples arrayed horizontally over the cavity opening, and vertically along the side walls. The pressure difference between the inside and outside of the cavity along the depth was also measured. It is found that the temperature rise of plume at the cavity opening is well scaled by the nondimensional temperature defined as ? = (?T/ T?. ) /Q*2/3 where Q* = Q/r? Cr T? ?gDD2, and the temperature is correlated by ? = a (H/ D)', where ?=-5/3, -1 and -1/3 for shallow, intermediate and deep cavity, respectively.