The main objective of this study was to develop a heat storage gypsum-cement board (G/C board) by using vacuum impregnation method and evaluate its physical and thermal properties. In particular, this paper analyzed the chemical property, heat capacity, thermal resistance, thermal conductivity, and heat transfer performance of the heat storage G/C board based on results of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA), TCi, and dynamic heat transfer analyses. Especially, dynamic heat transfer analysis was focused in this study to determine time-lag effect and thermal efficiency property of the developed heat storage G/C board with PCMs. As a result, it was confirmed that PCM containing heat storage G/C boards had time lag effect. Such heat storage G/C board could be used to reduce energy consumption of buildings. In the analysis of building energy consumption through energy simulation, the energy reduction effect is larger when the G/C board with n-octadecane was applied, because n-octadecane has more suitable phase change temperature. Especially, when n-octadecane was applied, it is effective to reduce the cooling load during cooling season. (C) 2019 Elsevier B.V. All rights reserved.