A composite phase change material (CPCM) of myristic acid/palmitic acid/sodium myristate (MA/PA/SM) has been proposed by impregnating a porous material of purified damar gum, also called Shorea javanica (SJ), to improve the thermal conductivity of CPCM. The thermal properties, thermal conductivity and thermal stability, of CPCM were measured using differential scanning calorimetry (DSC) thermal analysis, hot-disc thermal conductivity analyzer, and simultaneous thermal analyzer (STA). Moreover, a chemical reaction between fatty acid binary mixture and SJ in CPCM was evaluated by Fourier transform infra-red (FT-IR) spectrophotometer. The results of this study showed that the thermal conductivity of MA/PA/SM/SJ composite phase change material (CPCM) was improved by addition of 3 wt.% of Shorea javanica into MA/PA/SM eutectic mixture without showing a significant change in the thermophysical properties of CPCM. Moreover, the eutectic CPCM also does not show occurrence of chemical reaction between MA/PA/SM and SJ, and it has a good thermal performance and thermal stability. Therefore, the MA/PA/SM/SJ CPCM proposed in this study can be recommended as a new novelty material for thermal energy storage application.