In this research, porous wood flour (WF) and a eutectic mixture of lauric acid (LA) and myristic acid (MA) were prepared as a form-stable phase change material (FSPCM) using a vacuum impregnation method. The effects of alkali (NaOH), cetyltrimethylammonium bromide, and complex salts (CS) on the pore size of the WF were investigated. The results showed that the CS-treated WF (CS-WF) achieved the maximum pore size and impregnation ratio. The characterization by Fourier-transform infrared spectrometer, X-ray photoelectron spectrometer, and X-ray diffractometer illustrated that the combination of the LA-MA eutectic mixture and the CS-WF was a physical combination. The differential scanning calorimetry results suggested that the optimum melting temperature and the latent heat of the CS-WF/LA-MA FSPCM were 33.1 degrees C and 98.2 kJ kg(-1) respectively. The maximum impregnation ratio of the LA-MA eutectic mixture into the CS-WF was 60.3%. In addition, the thermogravimetric analysis indicated that the CS-WF/LA-MA FSPCM had better thermal durability than the pure LA-MA. Moreover, the CS-WF/LA-MA FSPCM had excellent thermal reliability after 500 thermal cycles. Thus, the CS-treatment of the WF was considered an excellent modification method. The prepared CS-WF/LA-MA FSPCM has the potential for latent heat thermal energy storage applications in terms of the proper phase-transition properties.