A new kind of phase change material (PCM) for energy-storing wallboard is introduced in this paper. By establishing the one-dimensional nonlinear mathematical model for heat conduction of the PCM energy-storing wallboard and according to the "effective heat capacity method", simulation and calculation were made using the software MATLAB to analyze and solve the heat transfer problem of the PCM room. Meanwhile, the property can be found that the heat storing/releasing ability of the new PCM is significantly higher than that of ordinary materials by the experiment-based method. The result indicates that applying proper PCM to the inner surface of the north wall in the ordinary room can not only enhance the indoor thermal-comfort dramatically, but also increase the utilization rate of the solar radiation. So the heating energy consuming is decreased and the goal of saving energy has been achieved. If the parameters of the PCM is given as follows: the phase change temperature is set at 23 degrees C, the thickness is set at 30 mm, the phase change enthalpy is set at 60 kJ/kg, and the heating temperature is set at 20 degrees C, the energy-saving rate of heating season eta can get to 17% or higher. So the energy is effectively used and saved obviously. (C) 2007 Elsevier B.V. All rights reserved.