Abstract: With SiO₂ as the carrier, decanoic acid-palmitic acid as phase change material, decanoic acid-palmitic acid/SiO₂ phase change and humidity storage composites were prepared by sol-gel method. The performance were tested and characterized by using isothermal moisture adsorption and desorption method, cooling curve method, FTIR, SEM, laser particle size analyzer(LPSA), BET, TGA and DSC etc. The results show that carrier material SiO₂ of decanoic acid-palmitic acid/SiO₂ phase change and humidity storage composites with cage structure have a large number of microporous forming 3D space grid structure. It can both package and constraint with phase change materials by physical chimeric way of decanoic acid-palmitic acid and SiO₂, and adsorb water molecules by hydrophilic properties of SiO₂. It has good heat-moisture property. Decanoic acid-palmitic acid/SiO₂ phase change and humidity storage composites have smooth surface with no obvious depression, particle size is small and has good uniformity (particle size is 82.14 nm, micropore volume is 0.010 7 mL/g, micropore specific surface area is 25.16 m²/g, micropore average diameter is 26.63 nm),and it belongs to nanoscale organic phase change core material/inorganic matrix composite; phase change temperature is 19.88-23.13 ℃, phase change latent heat is 38.55-42.56 J/g, mass fraction of decanoic acid-palmitic acid is about 31.59%, it meets the comfort of the human body temperature range and is suitable for widely use in construction field.