Dimensional stability is a significant problem in particleboard. This study aims to analyze the effect of immersing particles in an acid solution on particleboard’s physical and mechanical properties made of kemenyan (Styrax sumatrana) wood and belangke (Gigantochloa pruriens) bamboo. The particles were immersed in each acid solution for 24 h, and then dried to reach 9% water content. The particleboard was made with a 25x25 cm2 with a target thickness and density of 1 cm and 0.70 g/cm3, respectively. After being made into sheets, the next step is hot pressing using a hot press machine that has set the temperature, time, and pressure at 160 °C, 5 min, and 30 kg/cm2, respectively. The results showed that immersion in the acid solution can stabilize the dimensions of the resulting particleboard but does not reduce the strength of the board. Several board properties have met the standards, such as density, thickness swelling, modulus of rupture, and internal bond.